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1.
Sensors (Basel) ; 22(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36502230

RESUMO

This paper presents the application of CORPS (coherently radiating periodic structures) for feeding CRA (concentric rings array) with a reduced number of phase shifters. The proposed design technique for the structure of concentric rings provides a better scanning capability with respect to other existing configurations. This design technique utilizes 2 × 3 or 4 × 7 CORPS networks depending on the configuration or the number of antenna elements in the phased array system. These CORPS networks are set strategically in the feeding network to provide several advantages with respect to others in the scanning capability and the reduction of the number of phase shifters of the array system. The contribution of this paper is the full antenna system design of phased CRA for analyzing scanning and the reduction of phase shifters. The proposed phased array reduces the number of phase shifter devices in CRA for a scanning range of ±25° in the elevation plane. Differential evolution (DE) was applied to optimize the amplitudes of the proposed system. Several design cases were analyzed using full-wave simulation results to verify the phased array model and to take mutual coupling into account. Full-wave simulation results provide radiation patterns with low SLL in all scanning directions. The proposed phased array was validated by experimental measurements of the full antenna system prototype.


Assuntos
Simulação por Computador
2.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365903

RESUMO

This paper presents a new scheme of applying CORPS (coherently radiating periodic structures) for reducing the number of phase shifters in linear antenna arrays. This scheme can be seen as a combination of the properties of two techniques: CORPS and butler. The proposed system applies an interleaving of several blocks of 2 × 3 CORPS networks. This interleaving of two stages of 2 × 3 CORPS networks is made in a convenient way to provide the required progressive phase for beam-scanning and the level of amplitude excitations necessary for achieving the radiation characteristics of low SLL. Interesting results are provided based on experimental measurements and full-wave simulations to analyze and evaluate the performance of the feeding network based on CORPS and the reduction capability of the number of phase shifters in the antenna system. The proposed design methodology achieves a reduction capability of 66% in the number of phase shifters used in linear antenna arrays. This reduction in the complexity of the antenna system is reached maintaining a peak SLL of -22 dB with scanning ranges of until ±25°. A good design option is provided to simplify the complexity of the feeding network in antenna array applications.


Assuntos
Transição de Fase , Tecnologia sem Fio
3.
Front Mol Biosci ; 8: 715765, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513923

RESUMO

Background and Aims: Activation of the inflammasome NLRP3 (NOD-, LRR- and pyrin domain containing 3) contributes to the development of non-alcoholic fatty liver disease (NAFLD) and progression to non-alcoholic steatohepatitis (NASH). Therefore, this study explored the therapeutic effects of a novel and selective NLRP3 antagonist in a murine dietary model of NASH. Methods: Groups of 12-week-old ApoE -/- mice were fed ad lib for 7 weeks with a methionine/choline deficient (MCD) and western diet (WD). After 3 weeks of diet-induced injury, mice were injected i. p. with the NLRP3 antagonist IFM-514 (100 mg/kg body weight) or vehicle (0.5% carmellose) every day, 5 days/week for a further 4 weeks. Several markers of inflammation, fibrosis and steatosis were evaluated. Whole transcriptome sequencing and panel RNA expression analysis (NanoString) were performed. Results: IFM-514 inhibited IL-1ß production in mice challenged with 20 mg/kg lipopolysaccharide, and in mouse and human inflammatory cells in vitro. IFM-514 inhibited hepatic inflammation in the in vivo non-alcoholic steatohepatitis model assessed by H&E staining and in the hepatic gene expression of inflammasome-related proinflammatory cytokines. This effect was associated with significant reduction in caspase-1 activation. Similarly, IFM-514 was efficacious in vivo in MDC-fed ApoE -/- mice, markedly reducing portal pressure, Sirius red staining and 4-hydroxyproline content compared to vehicle-treated mice. Moreover, IFM-514 significantly reduced hepatic steatosis in MCD-fed ApoE -/- mice, as evidenced by NAFLD scores, oil red O staining, hepatic triglycerides and gene expression. In WD treated animals, similar trends in inflammation and fibrosis were observed, although not sufficient IFM-514 levels were reached. Conclusion: Overall, IFM-514 reduced liver inflammation and fibrosis, with mild effects on liver steatosis in experimental murine NASH. Blocking of NLRP3 may be an attractive therapeutic approach for NASH patients.

4.
J Immunol ; 198(7): 2735-2746, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28242647

RESUMO

Integration of signaling and metabolic pathways enables and sustains lymphocyte function. Whereas metabolic changes occurring during T cell activation are well characterized, the metabolic demands of differentiated T lymphocytes are largely unexplored. In this study, we defined the bioenergetics of Th17 effector cells generated in vivo. These cells depend on oxidative phosphorylation (OXPHOS) for energy and cytokine production. Mechanistically, the essential role of OXPHOS in Th17 cells results from their limited capacity to increase glycolysis in response to metabolic stresses. This metabolic program is observed in mouse and human Th17 cells, including those isolated from Crohn disease patients, and it is linked to disease, as inhibiting OXPHOS reduces the severity of murine colitis and psoriasis. These studies highlight the importance of analyzing metabolism in effector lymphocytes within in vivo inflammatory contexts and suggest a therapeutic role for manipulating OXPHOS in Th17-driven diseases.


Assuntos
Diferenciação Celular/imunologia , Colite/imunologia , Ativação Linfocitária/imunologia , Fosforilação Oxidativa , Células Th17/imunologia , Animais , Separação Celular , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
6.
Nat Chem Biol ; 11(2): 141-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25558972

RESUMO

Retinoic acid receptor-related orphan receptor γ (RORγt) controls the differentiation of naive CD4(+) T cells into the TH17 lineage, which are critical cells in the pathogenesis of autoimmune diseases. Here we report that during TH17 differentiation, cholesterol biosynthesis and uptake programs are induced, whereas their metabolism and efflux programs are suppressed. These changes result in the accumulation of the cholesterol precursor, desmosterol, which functions as a potent endogenous RORγ agonist. Generation of cholesterol precursors is essential for TH17 differentiation as blocking cholesterol synthesis with chemical inhibitors at steps before the formation of active precursors reduces differentiation. Upon activation, metabolic changes also lead to production of specific sterol-sulfate conjugates that favor activation of RORγ over the TH17-inhibiting sterol receptor LXR. Thus, TH17 differentiation is orchestrated by coordinated sterol synthesis, mobilization and metabolism to selectively activate RORγ.


Assuntos
Diferenciação Celular/fisiologia , Colesterol/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Células Th17/citologia , Animais , Linfócitos T CD4-Positivos/citologia , Linhagem da Célula , Colesterol/biossíntese , Colesterol/química , Desmosterol/análogos & derivados , Desmosterol/química , Desmosterol/metabolismo , Interleucina-17/biossíntese , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Células Sf9 , Spodoptera
7.
Chemosphere ; 120: 750-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25465958

RESUMO

Pharmaceuticals and personal care products (PPCPs) have raised concerns due to their potential effects to aquatic organisms. These chemicals appear in mixtures at very low concentrations thus making their detection and quantification difficult. Polar organic chemical integrative samplers (POCIS) concentrate trace levels of chemicals over time increasing method sensitivity and thus represent a cost-effective screening tool for biomonitoring studies. The Baca National Wildlife Refuge (BNWR), Colorado, is home for several endemic fish species, including Rio Grande chub (Gila pandora). The objectives of this study were to (1) determine the types and concentrations of PPCPs in the Refuge, (2) compare and contrast two methods (grab and POCIS) for the quantification of PPCPs from surface water, and (3) determine effects due to PPCP exposure in fish. Between 2011 and 2013, 141 PPCPs were quantified using a combination of grab samples and POCIS. Although no PPCPs were detected from the grab samples, high concentrations of N,N-Diethyl-meta-toluamide (DEET) and triclosan were detected in all fish sampling sites with POCIS. Fathead minnows (Pimephales promelas) and Rio Grande chubs of both sexes were collected in 2011 and 2012. Several biological responses were observed in both species from creeks contaminated with PPCPs; however the presence of PPCPs in the reference site did not allow for valid data comparison and interpretation. We conclude that POCIS is a sensitive method for the detection and quantification of PPCPs and for identification of reference sites and that appropriate "reference" sites need to be identified at the BNWR for follow-up studies with native fish.


Assuntos
Cosméticos/análise , Cyprinidae/metabolismo , Monitoramento Ambiental/estatística & dados numéricos , Água Doce/química , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Análise de Variância , Animais , Cromatografia Líquida , Colorado , Conservação dos Recursos Naturais , Cosméticos/farmacocinética , Monitoramento Ambiental/métodos , Feminino , Masculino , Compostos Orgânicos/análise , Compostos Orgânicos/farmacocinética , Preparações Farmacêuticas/metabolismo , Reação em Cadeia da Polimerase , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/farmacocinética
8.
J Pharmacol Exp Ther ; 351(2): 298-307, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25125579

RESUMO

T-cell activation requires increased ATP and biosynthesis to support proliferation and effector function. Most models of T-cell activation are based on in vitro culture systems and posit that aerobic glycolysis is employed to meet increased energetic and biosynthetic demands. By contrast, T cells activated in vivo by alloantigens in graft-versus-host disease (GVHD) increase mitochondrial oxygen consumption, fatty acid uptake, and oxidation, with small increases of glucose uptake and aerobic glycolysis. Here we show that these differences are not a consequence of alloactivation, because T cells activated in vitro either in a mixed lymphocyte reaction to the same alloantigens used in vivo or with agonistic anti-CD3/anti-CD28 antibodies increased aerobic glycolysis. Using targeted metabolic (13)C tracer fate associations, we elucidated the metabolic pathway(s) employed by alloreactive T cells in vivo that support this phenotype. We find that glutamine (Gln)-dependent tricarboxylic acid cycle anaplerosis is increased in alloreactive T cells and that Gln carbon contributes to ribose biosynthesis. Pharmacological modulation of oxidative phosphorylation rapidly reduces anaplerosis in alloreactive T cells and improves GVHD. On the basis of these data, we propose a model of T-cell metabolism that is relevant to activated lymphocytes in vivo, with implications for the discovery of new drugs for immune disorders.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Isoantígenos/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antígenos CD28/imunologia , Complexo CD3/imunologia , Ciclo do Ácido Cítrico/imunologia , Feminino , Glutamina/metabolismo , Glicólise/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Camundongos , Fosforilação Oxidativa , Ribose/biossíntese
9.
Environ Toxicol Chem ; 33(4): 910-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24375658

RESUMO

Pharmaceuticals and personal care products (PPCPs) have been detected widely in aquatic ecosystems, but little is known about their mechanisms of toxicity. We exposed adult fathead minnows (Pimephales promelas) for 48 h to triclocarban (1.4 µg/L), N,N-diethyl-meta-toluamide (DEET; 0.6 µg/L), or a mixture of PPCPs consisting of atenolol (1.5 µg/L), caffeine (0.25 µg/L), diphenhydramine (0.1 µg/L), gemfibrozil (1.5 µg/L), ibuprofen (0.4 µg/L), naproxen (1.6 µg/L), triclosan (2.3 µg/L), progesterone (0.2 µg/L), triclocarban (1.4 µg/L), and DEET (0.6 µg/L). Quantitative real-time polymerase chain reaction revealed an upregulation in vitellogenin (vtg) in livers of females and males exposed to triclocarban. Also, an upregulation of hepatic lipoprotein lipase (lpl) and a downregulation of androgen receptor (ar) and steroidogenic acute regulatory protein (star) were observed in testes. The group treated with DEET only showed a significant decrease in ar in females. In contrast, the PPCP mixture downregulated vtg in females and males and expression of estrogen receptor alpha (erα), star, and thyroid hormone receptor alpha 1 (thra1) in testes. The authors' results show that the molecular estrogenic effects of triclocarban are eliminated (males) or reversed (females) when dosed in conjunction with several other PPCP, once again demonstrating that results from single exposures could be vastly different from those observed with mixtures. Environ Toxicol Chem 2014;33:910-919. © 2013 SETAC.


Assuntos
Carbanilidas/toxicidade , Cosméticos/toxicidade , Cyprinidae/genética , DEET/toxicidade , Estrogênios/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Vitelogeninas/genética
10.
Bioorg Med Chem Lett ; 23(11): 3443-7, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23597790

RESUMO

Selective phosphodiesterase 2 (PDE2) inhibitors are shown to have efficacy in a rat model of osteoarthritis (OA) pain. We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of phosphodiesterase 4 (PDE4) inhibitors, while minimizing PDE4 inhibitory activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like binding mode orthogonal to the cAMP-like binding mode found in PDE4. Extensive structure activity relationship studies ultimately led to identification of pyrazolodiazepinone, 22, which was >1000-fold selective for PDE2 over recombinant, full length PDEs 1B, 3A, 3B, 4A, 4B, 4C, 7A, 7B, 8A, 8B, 9, 10 and 11. Compound 22 also retained excellent PDE2 selectivity (241-fold to 419-fold) over the remaining recombinant, full length PDEs, 1A, 4D, 5, and 6. Compound 22 exhibited good pharmacokinetic properties and excellent oral bioavailability (F=78%, rat). In an in vivo rat model of OA pain, compound 22 had significant analgesic activity 1 and 3h after a single, 10 mg/kg, subcutaneous dose.


Assuntos
Azepinas/química , Azirinas/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Di-Hidropiridinas/química , Inibidores de Fosfodiesterase/química , Pirazóis/química , Analgésicos/química , Analgésicos/farmacocinética , Analgésicos/uso terapêutico , Animais , Azepinas/farmacocinética , Azepinas/uso terapêutico , Azirinas/farmacocinética , Azirinas/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Di-Hidropiridinas/farmacocinética , Di-Hidropiridinas/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Osteoartrite/tratamento farmacológico , Inibidores da Fosfodiesterase 4/química , Inibidores de Fosfodiesterase/farmacocinética , Inibidores de Fosfodiesterase/uso terapêutico , Ligação Proteica , Pirazóis/farmacocinética , Pirazóis/uso terapêutico , Ratos , Relação Estrutura-Atividade
11.
Bioorg Med Chem Lett ; 23(11): 3438-42, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23582272

RESUMO

We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of PDE4 inhibitors, while simultaneously minimizing PDE4 activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like mode in contrast to the cAMP-like binding mode found in PDE4. Structure activity relationship studies coupled with an inhibitor bound crystal structure in the active site of the catalytic domain of PDE2 identified structural features required to minimize PDE4 inhibition while simultaneously maximizing PDE2 inhibition.


Assuntos
Azirinas/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Di-Hidropiridinas/química , Inibidores da Fosfodiesterase 4/química , Inibidores de Fosfodiesterase/química , Animais , Azirinas/metabolismo , Azirinas/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Di-Hidropiridinas/metabolismo , Di-Hidropiridinas/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Osteoartrite/tratamento farmacológico , Inibidores de Fosfodiesterase/metabolismo , Inibidores de Fosfodiesterase/uso terapêutico , Ligação Proteica , Relação Estrutura-Atividade
12.
Environ Toxicol Chem ; 30(5): 1197-203, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21309028

RESUMO

Proteomics has gained popularity in the field of ecotoxicology as a holistic tool for unraveling novel mechanisms of toxicity and elucidating subtle effects of contaminant exposure. The holoarctic amphipod Diporeia spp. is declining at precipitous rates in the Great Lakes, and we are evaluating the use of the well-studied amphipod model Hyalella azteca as a surrogate for Diporeia spp. This article presents proteomics data from both amphipod species exposed to atrazine (ATZ) and one of its metabolites, desethylatrazine (DEA; 3 and 30 µg/L for 21 and 42 d). We used a proteomics approach to determine whether these two species of amphipods responded similarly to the same chemicals and to understand better the mechanisms of toxicity of ATZ and DEA in aquatic invertebrates. We observed disruption in energy production and mitochondrial function as well as hormesis in exposed organisms. In addition, we identified a two proteins (GAPDH and HSP 90 kDa) that have been linked to hormonal disruptions, suggesting potential endocrine disruption. Finally, we found that H. azteca and Diporeia spp. responded with similar proteomic profiles after ATZ and DEA exposure, suggesting that H. azteca may be used as a surrogate model organism for Diporeia spp.


Assuntos
Anfípodes/efeitos dos fármacos , Atrazina/toxicidade , Herbicidas/toxicidade , Proteoma/metabolismo , Poluentes Químicos da Água/toxicidade , Anfípodes/metabolismo , Animais , Especificidade da Espécie
13.
Environ Toxicol Chem ; 30(2): 274-82, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21072841

RESUMO

Over the last decade, the environmental sciences have witnessed an incredible movement towards the utilization of high-throughput molecular tools that are capable of detecting simultaneous changes of hundreds, and even thousands, of molecules and molecular components after exposure of organisms to different environmental stressors. These techniques have received a great deal of attention because they not only offer the potential to unravel novel mechanisms of physiological and toxic action but are also amenable to the discovery of biomarkers of exposure and effects. In this article, we review the state of knowledge of one of these tools in ecotoxicological research: proteomics. We summarize the state of proteomics research in fish, and follow with studies conducted with aquatic invertebrates. A brief discussion on proteomic methods is also presented. We conclude with some ideas for future proteomic studies with fish and aquatic invertebrates.


Assuntos
Ecotoxicologia/métodos , Hidrobiologia/métodos , Proteômica/métodos , Animais , Peixes , Invertebrados
14.
J Appl Toxicol ; 31(2): 108-16, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20589742

RESUMO

Microarrays enable gene transcript expression changes in near-whole genomes to be assessed in response to environmental stimuli. We utilized oligonucleotide microarrays and subsequent gene set enrichment analysis (GSEA) to assess patterns of gene expression changes in male largemouth bass (Micropterus salmoides) hepatic tissues after a 96 h exposure to common environmental contaminants. Fish were exposed to atrazine, cadmium chloride, PCB 126, phenanthrene and toxaphene via intraperitoneal injection with target body burdens of 3.0, 0.00067, 2.5, 50 and 100 µg g(-1), respectively. This was conducted in an effort to identify potential biomarkers of exposure. The expressions of 4, 126, 118, 137 and 58 mRNA transcripts were significantly (P ≤ 0.001, fold change ≥2×) affected by exposure to atrazine, cadmium chloride, PCB 126, phenanthrene and toxaphene exposures, respectively. GSEA revealed that none, four, five, five and three biological function gene ontology categories were significantly influenced by exposure to these chemicals, respectively. We observed that cadmium chloride elicited ethanol metabolism responses, and along with PCB 126 and phenanthrene affected transcripts associated with protein biosynthesis. PCB 126, phenanthrene and toxaphene also influenced one-carbon compound metabolism while PCB 126 and phenanthrene affected mRNA transcription and mRNA export from the nucleus and may have induced an antiestrogenic response. Atrazine was found to alter the expression of few hepatic transcripts. This work has highlighted several biological processes of interest that may be helpful in the development of gene transcript biomarkers of chemical exposure in fish.


Assuntos
Bass/metabolismo , Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Biomarcadores , Carga Corporal (Radioterapia) , Exposição Ambiental , Poluentes Ambientais/análise , Perfilação da Expressão Gênica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Estatística como Assunto
15.
Aquat Toxicol ; 95(1): 1-9, 2009 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-19781795

RESUMO

Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens (microg/g): atrazine (0.3 and 3.0), toxaphene (10 and 100), cadmium (CdCl(2)) (0.000067 and 0.00067), polychlorinated biphenyl (PCB) 126 (0.25 and 2.5), and phenanthrene (5 and 50). Partial largemouth bass gene segments were cloned for enzymes involved in neurotransmitter (glutamic acid decarboxylase 65, GAD65; tyrosine hydroxylase) and estrogen (brain aromatase; CYP19b) synthesis for real-time PCR assays. In addition, neuropeptides regulating feeding (neuropeptide Y) and reproduction (chicken GnRH-II, cGnRH-II; salmon GnRH, sGnRH) were also investigated. Of the chemicals tested, only cadmium, PCB 126, and phenanthrene showed any significant effects on the genes tested, while atrazine and toxaphene did not. Cadmium (0.000067 microg/g) significantly increased cGnRH-II mRNA while PCB 126 (0.25 microg/g) decreased GAD65 mRNA. Phenanthrene decreased GAD65 and tyrosine hydroxylase mRNA levels at the highest dose (50 microg/g) but increased cGnRH-II mRNA at the lowest dose (5 microg/g). CYP19b, NPY, and sGnRH mRNA levels were unaffected by any of the treatments. A hierarchical clustering dendrogram grouped PCB 126 and phenanthrene more closely than other chemicals with respect to the genes tested. This study demonstrates that brain transcripts important for neurotransmitter synthesis neuroendocrine function are potential targets for emerging and prevalent aquatic contaminants.


Assuntos
Bass/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Gonadotropinas/metabolismo , Neurotransmissores/genética , Poluentes Químicos da Água/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Masculino , Poluentes Químicos da Água/análise
16.
Aquat Toxicol ; 95(1): 52-9, 2009 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-19717195

RESUMO

Liver proteome response of largemouth bass (Micropterus salmoides) exposed to environmental contaminants was analyzed to identify novel biomarkers of exposure. Adult male bass were exposed to cadmium chloride (CdCl(2)), atrazine, PCB 126, phenanthrene, or toxaphene via intraperitoneal injection with target body burdens of 0.00067, 3.0, 2.5, 50, and 100 microg/g, respectively. After a 96 h exposure, hepatic proteins were separated with two-dimensional gel electrophoresis and differentially expressed proteins (vs. controls) recognized and identified with MALDI-TOF/TOF mass spectrometry. We identified, 30, 18, eight, 19, and five proteins as differentially expressed within the CdCl(2), atrazine, PCB 126, phenanthrene, and toxaphene treatments, respectively. Alterations were observed in the expression of proteins associated with cellular ion homeostasis (toxaphene), oxidative stress (phenanthrene, PCB 126), and energy production including glycolysis (CdCl(2), atrazine) and ATP synthesis (atrazine). This work supports the further evaluation of several of these proteins as biomarkers of contaminant exposure in fish.


Assuntos
Bass/fisiologia , Biomarcadores/análise , Exposição Ambiental , Fígado/efeitos dos fármacos , Proteômica , Poluentes Químicos da Água/toxicidade , Animais , Bass/metabolismo , Eletroforese em Gel Bidimensional , Masculino , Poluentes Químicos da Água/análise
17.
Environ Sci Technol ; 42(18): 7010-7, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18853824

RESUMO

The detection of harmful chemicals and biological agents in real time is a critical need for protecting freshwater ecosystems. We studied the real-time effects of five environmental contaminants with differing modes of action (atrazine, cadmium chloride, pentachlorophenol, malathion, and potassium cyanide) on respiratory oxygen consumption in 2-day postfertilization fathead minnow (Pimephales promelas) eggs. Our objective was to assess the sensitivity of fathead minnow eggs using the self-referencing micro-optrode technique to detect instantaneous changes in oxygen consumption after brief exposures to low concentrations of contaminants. Oxygen consumption data indicated that the technique is indeed sensitive enough to reliably detect physiological alterations induced by four of the five contaminants. After 2 h of exposure, we identified significant increases in oxygen consumption upon exposure to pentachlorophenol (100 and 1000 microg/L), cadmium chloride (0.0002 and 0.002 microg/L), and atrazine (150 microg/L). In contrast, we observed a significant decrease in oxygen flux after exposuresto potassium cyanide (44 and 66 microg/L) and atrazine (1500 microg/L). No effects were detected after exposures to malathion (200 and 340 microg/L). Our work is the first step in development of a new technique for physiologically coupled biomonitoring as a sensitive and reliable tool for the detection of environmental toxicants.


Assuntos
Técnicas Biossensoriais/métodos , Cyprinidae/embriologia , Cyprinidae/metabolismo , Embrião não Mamífero/metabolismo , Oxigênio/metabolismo , Estresse Fisiológico , Água/normas , Animais , Atrazina/farmacologia , Cloreto de Cádmio/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Exposição Ambiental , Malation/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Pentaclorofenol/farmacologia , Cianeto de Potássio/farmacologia , Rotenona/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo
18.
J Pharmacol Toxicol Methods ; 57(3): 169-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18367413

RESUMO

INTRODUCTION: Thermal imaging has been utilized, both preclinically and clinically, as a tool for assessing inflammation and arthritis. However, previous studies have employed large, relatively immobile devises to obtain the thermal signature of the tissue of interest. The present study describes the characterization of a hand-held thermal imaging device in a preclinical model of general inflammation and a model of rheumatoid arthritis (RA). METHODS: A hand-held ThermoView Ti30 portable thermal imager was utilized to detect the temporal changes in thermal signatures in rat model of carrageenan-induced paw edema (CFE) and a model of collagen-induced arthritis (CIA). In both in vivo models, the kinetics of the thermal changes were correlated to footpad swelling. In addition, the CFE model was utilized to examine the ability of this technology to delineate pharmacodynamic changes in thermal signature in response to the non-steroidal anti-inflammatory drug indomethacin (10 mg/kg; p.o.). RESULTS: Thermal analysis of rat paws in the CFE model demonstrated a significant increase in the mean temperature difference between the inflamed and contralateral control paw by two hours post-carrageenan (8.3 +/-0.5 degrees F). Indomethacin significantly decreased the mean temperature difference in treated animals as compared to vehicle. In the rat CIA model, increases in footpad temperature, as determined by thermal imaging, were significantly elevated by Day 11 and remained elevated throughout the duration of the 28 day protocol. Thermal changes were also found to precede increases in footpad edema (swelling). DISCUSSION: The results of this study demonstrate that the hand-held thermal imaging technology represents a rapid, highly-reproducible method by which to quantitate the degree of inflammation in rat models of general inflammation and rheumatoid arthritis. The ability to detect pharmacodynamic responses in paw temperature suggests that this technology may be a useful tool for the development of pharmacologic interventions for the treatment inflammation-related pathologies.


Assuntos
Artrite Experimental/diagnóstico , Inflamação/diagnóstico , Termografia/métodos , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/induzido quimicamente , Artrite Experimental/tratamento farmacológico , Carragenina , Colágeno , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/diagnóstico , Edema/tratamento farmacológico , Feminino , Membro Posterior , Indometacina/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Masculino , Ratos , Ratos Sprague-Dawley
19.
Environ Toxicol Chem ; 27(3): 617-22, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17967068

RESUMO

Risk of polychlorinated biphenyl (PCB) exposure and effects were assessed for a colony of federally endangered interior least terns (Sterna antillarum) nesting on the Bitter Lake National Wildlife Refuge (NM, USA). The colony feeds from an area on the Refuge (Hunter Marsh/Oxbow Complex) wherein fish with elevated concentrations of total PCBs have been documented. Concentrations of total PCBs in whole fish averaged 0.94 mg/kg with a maximum concentration of 2.77 mg/kg, wet weight. Estimated daily PCB intake rates by adult birds throughout their 180-d breeding season ranged from <0.01 mg/kg/d to 0.98 mg/ kg/d, yielding hazard quotients that ranged from 0.01 to 21.68. Polychlorinated biphenyls pose a moderate risk to the colony of interior least terns that breed at the Bitter Lake National Wildlife Refuge, but the exposure rate is not likely to threaten their overall breeding success.


Assuntos
Charadriiformes/metabolismo , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Animais , Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Peixes/metabolismo , Cadeia Alimentar , Contaminação de Alimentos , New Mexico , Óvulo , Fatores de Risco
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