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2.
Sci Total Environ ; 438: 527-32, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23037812

RESUMO

Brown pelicans (Pelecanus occidentalis) were listed as endangered in the United States in 1970, largely due to reproductive failure and mortality caused by organochlorine contaminants, such as DDT. The southeast population, P.o. carolinensis, was delisted in 1985, while the west coast population, P.o. californicus, was not delisted until 2009. As fish-eating coastal seabirds, brown pelicans may serve as a biomonitors. Organic contaminants were examined in brown pelican eggs collected from the Gulf of California in 2004 and South Carolina in 2005 using gas chromatography/mass spectrometry (GC/MS). Contaminants were compared using all individual data as well as statistically pooled samples to provide similar sample sizes with little difference in results. Principal components analysis separated the Gulf of California brown pelican eggs from the South Carolina eggs based on contaminant patterns. The South Carolina population had significantly (P<0.05) higher levels of polychlorinated biphenyls (PCBs), chlordanes, dieldrin and mirex, while the Gulf of California eggs had higher levels of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs). With the exception of dieldrin and brominated diphenyl ether (BDE) 47, this pattern was observed for mussel and oyster tissues from these regions, indicating the need for further study into the differences between east and west coast brown pelican populations and ecosystem contamination patterns.


Assuntos
Aves , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Óvulo/química , Análise de Variância , Animais , Clordano/análise , DDT/análise , Dieldrin/análise , Monitoramento Ambiental/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Hexaclorocicloexano/análise , Limite de Detecção , México , Mirex/análise , Análise Multivariada , Oceanos e Mares , Bifenilos Policlorados/análise , Análise de Componente Principal , South Carolina
3.
Reprod Toxicol ; 27(3-4): 307-318, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19071210

RESUMO

Studies show that perfluorinated compounds cause various toxicological effects; nevertheless, effects on immune function and developmental endpoints have not been addressed at length. This study examined the effects of perfluorooctane sulfonate (PFOS) in white leghorn hatchlings on various developmental, immunological, and clinical health parameters. In addition, serum PFOS concentrations were determined by LC/MS/MS. Embryonic day (ED) 0 eggs were injected with either safflower oil/10% DMSO (control, 0mg/kg egg wt) or PFOS in safflower oil/10% DMSO at 1, 2.5, or 5mg/kg egg wt, and the chicks were grown to post-hatch day (PHD) 14. Treatment with PFOS did not affect hatch rate. Following in ovo exposure chicks exhibited increases in spleen mass at all treatment levels, in liver mass at 2.5 and 5mg/kg egg wt, and in body length (crown-rump length) at the 5mg/kg treatment. Right wings were shorter in all treatments compared to control. Increases in the frequency of brain asymmetry were evident in all treatment groups. SRBC-specific immunoglobulin (IgM and IgY combined) titers were decreased significantly at all treatment levels, while plasma lysozyme activity was increased at all treatment levels. The PHA skin test response decreased in relation to increasing PFOS dose. Serum concentrations where significant immunological, morphological, and neurological effects were observed at the lowest dose (1mg/kg egg wt) averaged 154 ng PFOS/g serum. These concentrations fall within environmental ranges reported in blood samples from wild caught avian species; thereby, verifying that the environmental egg concentrations used for the injections do indeed relate to serum levels in hatchlings that are also environmentally relevant. These data indicate that immune alterations and brain asymmetry can occur in birds following in ovo exposure to environmentally relevant concentrations of PFOS and demonstrates the need for further research on the developmental effects of perfluorinated compounds in various species.


Assuntos
Anormalidades Induzidas por Medicamentos , Ácidos Alcanossulfônicos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Fluorocarbonos/toxicidade , Óvulo/efeitos dos fármacos , Ácidos Alcanossulfônicos/farmacologia , Animais , Embrião de Galinha , Galinhas , Estatura Cabeça-Cóccix , Relação Dose-Resposta a Droga , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Poluentes Ambientais/farmacologia , Feminino , Fluorocarbonos/farmacologia , Fígado/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Baço/efeitos dos fármacos , Asas de Animais/efeitos dos fármacos
4.
Vet Immunol Immunopathol ; 118(3-4): 199-209, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17614139

RESUMO

Florida manatees (Trichechus manatus latirostris) are exposed to many conditions in their habitat that may adversely impact health and impair immune function in this endangered species. In an effort to increase the current knowledge base regarding the manatee immune system, the production of an important reactive nitrogen intermediate, nitric oxide (NO), by manatee peripheral blood mononuclear cells (PBMC) was investigated. PBMC from healthy captive manatees were stimulated with LPS, IFN-gamma, or TNF-alpha, either alone or in various combinations, with NO production assessed after 24, 48, 72, and 96 h of culture. NO production in response to LPS stimulation was significantly greater after 48, 72, or 96 h of culture compared to NO production after 24h of culture. A specific inhibitor of inducible nitric oxide synthase (iNOS), L-NIL (L-N(6)-(1-iminoethyl)lysine), significantly decreased NO production by LPS-stimulated manatee PBMC. Manatee specific oligonucleotide primers for iNOS were designed to measure expression of relative amounts of mRNA in LPS-stimulated manatee PBMC from captive manatees. NO production by PBMC from manatees exposed to red tide toxins was analyzed, with significantly greater NO production by both unstimulated and LPS stimulated PBMC from red tide exposed compared with healthy captive or cold-stress manatees. Free-ranging manatees produced significantly lower amounts of nitric oxide compared to either captive or red tide rescued manatees. Results presented in this paper contribute to the current understanding of manatee immune function and represent the first report of nitric oxide production in the immune system of a marine mammal.


Assuntos
Leucócitos Mononucleares/metabolismo , Óxido Nítrico/metabolismo , Trichechus manatus/sangue , Trichechus manatus/metabolismo , Animais , Temperatura Baixa , Dinoflagellida , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Lisina/análogos & derivados , Lisina/farmacologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fatores de Tempo
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