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1.
Environ Monit Assess ; 184(5): 3141-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21713478

RESUMO

The concentrations of cadmium, lead, manganese and zinc were determined in the fish species Micropogonias manni captured in Budi Lake, Araucanía Region (Chile). The measurements were made by atomic absorption spectroscopy, and the analysis considered the sex, weight and size of the species; the representative samples were taken from the liver and muscle tissue. The method was validated using certified reference material (DOLT-1). The ranges of concentrations found in the muscle tissue were: Cd, not determinate (n.d.)-0.26; Pb, n.d.-1.88; Mn, 0.02-12.17 and Zn, 0.48-39.04 mg kg(-1) (dry weight). The concentrations in muscle tissue were generally lower than those found in the liver. With respect to the average concentrations recorded for each metal in the edible part of the fish (muscle tissue), it was found that the levels of Cd, Pb, Mn and Zn are within the ranges published by other authors in similar works and below the maximum concentration limits permitted by current legislation (FAO/WHO 2004; EU 2001) and do not constitute a health hazard for consumers of this species. The results were subjected to statistical analysis to evaluate the correlations between the content of the various metals and the sex, weight and size of each sample.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Lagos/química , Metais Pesados/metabolismo , Perciformes/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Humanos , Fígado/metabolismo , Metais Pesados/análise , Músculos/metabolismo , Medição de Risco , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos
2.
Sci Total Environ ; 609: 724-734, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28763669

RESUMO

Land-use change is a principal factor affecting riparian vegetation and river biodiversity. In Chile, land-use change has drastically intensified over the last decade, with native forests converted to exotic forest plantations and agricultural land. However, the effects thereof on aquatic ecosystems are not well understood. Closing this knowledge gap first requires understanding how human perturbations affect riparian and stream biota. Identified biological indicators could then be applied to determine the health of fluvial ecosystems. Therefore, this study investigated the effects of land-use change on the health of riparian and aquatic ecosystems by assessing riparian vegetation, water quality, benthic macroinvertebrate assemblages, and functional feeding groups. Twenty-one sites in catchment areas with different land-uses (i.e. pristine forests, native forests, exotic forest plantations, and agricultural land) were selected and sampled during the 2010 to 2012 dry seasons. Riparian vegetation quality was highest in pristine forests. Per the modified Macroinvertebrate Family Biotic Index for Chilean species, the best conditions existed in native forests and the worst in agricultural catchments. Water quality and macroinvertebrate assemblages significantly varied across land-use areas, with forest plantations and agricultural land having high nutrient concentrations, conductivity, suspended solids, and apparent color. Macroinvertebrate assemblage diversity was lowest for agricultural and exotic forest plantation catchments, with notable non-insect representation. Collector-gatherers were the most abundant functional feeding group, suggesting importance independent of land-use. Land-use areas showed no significant differences in functional feeding groups. In conclusion, anthropogenic land-use changes were detectable through riparian quality, water quality, and macroinvertebrate assemblages, but not through functional feeding groups. These data, particularly the riparian vegetation and macroinvertebrate assemblage parameters, could be applied towards the conservation and management of riparian ecosystems through land-use change studies.


Assuntos
Monitoramento Ambiental , Invertebrados , Rios , Qualidade da Água , Agricultura , Animais , Biodiversidade , Chile , Florestas
3.
Neurosurgery ; 81(3): 416-421, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28368495

RESUMO

Traumatic brain and spinal cord injuries are major public health issues causing significant death and long-term disability in the United States, with higher incidences in young and older adults. The ThinkFirst National Injury Prevention Foundation is a nonprofit organization focused on injury prevention education and awareness for people of all ages, with a particular focus on educating children, teens, and young adults. ThinkFirst chapters have evaluated the effectiveness of the ThinkFirst programs in both children and teens by demonstrating significant improvement in knowledge regarding high-risk behaviors postintervention. Here, we review the available literature studying the efficacy of the ThinkFirst National Injury Prevention Foundation programs, outline current ThinkFirst activity, and discuss future directions of the program. This review discusses the efforts of a number of ThinkFirst chapters in terms of research, legislation, and public communication. It showcases the success of ThinkFirst interventions and suggests future directions which can help improve national injury prevention efforts.


Assuntos
Lesões Encefálicas Traumáticas/prevenção & controle , Educação em Saúde , Neurocirurgia , Traumatismos da Medula Espinal/prevenção & controle , Adolescente , Adulto , Criança , Humanos , Estados Unidos , Adulto Jovem
4.
PLoS One ; 11(5): e0154766, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27168069

RESUMO

BACKGROUND: Marine species have colonized extreme environments during evolution such as freshwater habitats. The amphidromous teleost fish, Galaxias maculatus is found mainly migrating between estuaries and rivers, but some landlocked populations have been described in lakes formed during the last deglaciation process in the Andes. In the present study we use mtDNA sequences to reconstruct the historical scenario of colonization of such a lake and evaluated the osmoregulatory shift associated to changes in habitat and life cycle between amphidromous and landlocked populations. RESULTS: Standard diversity indices including the average number of nucleotide differences (Π) and the haplotype diversity index (H) indicated that both populations were, as expected, genetically distinctive, being the landlocked population less diverse than the diadromous one. Similarly, pairwise GST and NST comparison detected statistically significant differences between both populations, while genealogy of haplotypes evidenced a recent founder effect from the diadromous stock, followed by an expansion process in the lake. To test for physiological differences, individuals of both populations were challenged with a range of salinities from 0 to 30 ppt for 8 days following a period of progressive acclimation. The results showed that the landlocked population had a surprisingly wider tolerance to salinity, as landlocked fish survival was 100% from 0 to 20 ppt, whereas diadromous fish survival was 100% only from 10 to 15 ppt. The activity of ATPase enzymes, including Na+/K+-ATPase (NKA), and H+-ATPase (HA) was measured in gills and intestine. Activity differences were detected between the populations at the lowest salinities, including differences in ATPases other than NKA and HA. Population differences in mortality are not reflected in enzyme activity differences, suggesting divergence in other processes. CONCLUSIONS: These results clearly demonstrate the striking adaptive changes of G. maculatus osmoregulatory system, especially at hyposmotic environments, associated to a drastic shift in habitat and life cycle at a scale of a few thousand years.


Assuntos
Aclimatação/fisiologia , Osmeriformes/fisiologia , Osmorregulação/fisiologia , Aclimatação/efeitos dos fármacos , Migração Animal/fisiologia , Animais , Teorema de Bayes , Biodiversidade , Evolução Biológica , Haplótipos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Macrolídeos/farmacologia , Osmorregulação/efeitos dos fármacos , Ouabaína/farmacologia , Dinâmica Populacional , ATPases Translocadoras de Prótons/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Análise de Sobrevida
5.
Fam Cancer ; 14(3): 415-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25782445

RESUMO

Lynch syndrome (LS) is an inherited form of colorectal cancer (CRC) caused by germline mutations in the mismatch repair (MMR) genes. It accounts for approximately 5% of all CRCs. The prevalence of LS among US Hispanics is unknown. The objective of this study was to describe the germline mutations of LS in Caribbean Hispanics from Puerto Rico and Dominican Republic. A total of 89 subjects were recruited through the Puerto Rico Familial Colorectal Cancer Registry and were classified according to Amsterdam and Bethesda clinical guidelines. For those tumors with lack of expression of MMR protein, gene sequencing was ordered. A total of 35 individuals with deficient MMR system were identified: 22 had MMR mutations and 13 had tumors with absent MMR protein expression. Our results show that the mutation spectrum of Caribbean Hispanic LS patients was composed mostly of MSH2 (66.7%) mutations, followed by MLH1 (25.0%). One mutation was identified in MSH6 (8.3%). A previously unidentified mutation in MLH1 gene c.2044_2045del was found in one Caribbean Hispanic family. MMR mutation-positive individuals were found to be more likely to have a prominent family history of CRC and tumors located at the proximal colon. Compared to MSH2 mutation carriers, MLH1 mutation-positive individuals were more likely to have a strong family history of CRC and LS associated cancers. Furthermore, insurance coverage for genetic testing was found to be limited in the study population with 65.1% of the individuals recruited were denied coverage. This report presents the first description of the mutation spectrum and clinicopathologic characteristics of LS Caribbean Hispanics patients.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/etiologia , Reparo de Erro de Pareamento de DNA/genética , Mutação , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Região do Caribe , Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Testes Genéticos/economia , Testes Genéticos/métodos , Mutação em Linhagem Germinativa , Hispânico ou Latino/genética , Humanos , Reembolso de Seguro de Saúde , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Síndrome de Muir-Torre/genética , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Proteína 2 Homóloga a MutS/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Porto Rico
6.
Interciencia ; 30(3): 120-125, mar. 2005. mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-432043

RESUMO

Eleginops maclovinus (Valenciennes, 1830) es un pez común en el litoral, estuarios y también ríos, preferentemente donde afectan las mareas, del sur de América del Sur, incluyendo las islas Malvinas. Se conoce su alimentación en los dos primeros hábitats, donde consume principalmente animales de ambiente marino y estuarino, donde se alimenta de fauna autóctona (mejillones, crustáceos, poliquetos, etc). Sin embargo, se desconoce su alimentación en ambientes limnéticos, suponiéndose que debería consumir presas propias de aquellos lugares. Es este estudio se analizaron 114 ejemplares de E. maclovinus, de los cuales 98 poseyeron estómagos con contenido. Se ratificó la tendencia zoofágica de la especie, pero también se comprobó que en ambientes limnéticos consume animales propios de bajas salinidades o salinidades limnéticas. El pez se presenta como una especie extraordinariamente versátil en sus capacidades tróficas, con una fisiología que le permite cubrir un amplio abanico ormorregulatorio a nivel digestivo, probablemente uno de las más variados en el suborden Notothenioidei, de supuesto orígen antártico


Assuntos
Animais , Ração Animal , Peixes , Rios , América do Sul , Equilíbrio Hidroeletrolítico , Chile , Biologia Marinha
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