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1.
Sci Total Environ ; 803: 149921, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482135

RESUMO

Plastic pollution poses a global threat to aquatic organisms, yet its effect on many species remains poorly documented and understood. This study addresses the impact caused by different sizes of polyethylene (PE) plastics on the common carp and evaluates their multi-biomarkers response. We investigated the histological structure and measurement of biochemical alterations, antioxidant enzymes, immunological responses, and fluctuations in blood profiles of the organisms after 15 days of exposure to a concentration of 100 mg/L of nano- (NPs), micro- (MPs) and macroplastics (MaPs). The fish health status was altered in the sole presence of PE particles. All biomarkers changed after exposure compared to the control group, with larger changes being observed with the decreasing size of particles (NPs > MPs > MaPs) compared to their absence. A synergistic effect resulting from the individual impact of plastics penetration in the circulatory system, bursting biochemical responses, and lesions in tissues, might explain the more considerable impact of NPs compared to MPs and/or MaPs.


Assuntos
Carpas , Poluentes Químicos da Água , Animais , Biomarcadores , Microplásticos , Plásticos , Polietileno , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
2.
Sci Total Environ ; 760: 143909, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341623

RESUMO

Rhodium and platinum are amongst the less studied elements in estuarine waters and the understanding of their speciation analysis and environmental fate remains limited. In this study, we address the occurrence and discrimination of soluble/insoluble Rh and Pt species in aquatic systems, as well as their potential transport. Particulate and dissolved (< 0.45 µm) rhodium (RhP and RhD) and platinum (PtP and PtD), respectively, were determined in the water column of contrasting environments during neap (NT) and spring (ST) tide semi-diurnal cycles: in the upper Tagus estuary (VFX) and near the mouth, close to a wastewater treatment plant outfall (ALC). Both elements were analyzed by AdCSV and ICP-MS, as well ancillary parameters were determined. Concentrations of Rh and Pt followed the tidal regime, presenting higher concentrations during low tide. Concentrations of RhP (0.1-5.1 ng g-1) and RhD (0.03-0.12 ng L-1) were lower than PtP (1.0-25.6 ng g-1) and PtD (0.1-11.7 ng L-1), respectively. Concentrations found in ALC were higher than VFX, except for RhD, mirroring anthropogenic inputs attributed to automotive catalytic converters and an additional Pt source originated in Pt-based compounds. Distribution coefficients (KD) of 104 were computed and were independent of the salinity gradient. The speciation analysis done at VFX during NT showed that truly dissolved forms measured by AdCSV represented 39 ± 9% of total Pt in the water column, while total filter-passing species measured by ICP-MS were higher, 65 ± 14%. Pt speciation was controlled by its dissolved forms, whereas particulate Rh forms represented the bulk value (> 65%). The potential transport evaluated at downstream station indicated recirculation within the estuary and export towards the Atlantic Ocean, with higher concentrations associated with the ebb opposing to the flood. These results show estuaries as important pathways to introduce PGE in coastal regions, transferring them towards the ocean.

4.
J Occup Environ Med ; 62(11): 965-972, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32868600

RESUMO

OBJECTIVE: To examine National Corrections Collaborative (NCC) activities, as an outreach initiative, to advance corrections workplace health and safety research, practice, and policy through a series of applied Research to Practice (r2p) meetings informed by the Total Worker Health(Total Worker Health is a registered trademark of the U.S. Department of Health and Human Services) (TWH) strategy. METHODS: We mapped the coalescence of correctional worker health concerns, federal and national professional organization initiatives, and research activities that formed the NCC in 2014. RESULTS: During the NCC's 5-years of TWH activities, attendance increased, partner composition expanded, and themes of concern evolved. Partners were motivated to participate and work together towards building evidence for health and safety r2p. CONCLUSIONS: A unified plea to the academic and federal research communities for assistance with better evaluation instruments, data linkages, and for adopting an integrated TWH approach to workforce health and wellbeing continue to drive NCC r2p activities.


Assuntos
Saúde do Trabalhador , Humanos , Local de Trabalho
5.
Sci Total Environ ; 722: 137954, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32208280

RESUMO

Road dust is a major reservoir of anthropogenic Pt and Rh. However, information about how these elements are released to the aquatic systems under environmentally relevant conditions is scarce. In this work, an innovative combination of analytical strategies is used to provide insight into the speciation analysis of those elements. A composite sample of road dust thoroughly characterized was incubated over 7 days in synthetic rainwater and seawater. In the filtered (<0.45 µm) solutions, truly dissolved Pt and Rh concentrations were measured by adsorptive cathodic stripping voltammetry, while total concentrations were determined by inductively coupled plasma mass spectrometry. Truly dissolved species corresponded to a small fraction of total Pt and Rh in the road dust; accordingly, values of 0.01% and 0.1% were obtained in both media for Pt and Rh, respectively, which remained constant over time. The concentration of total filter-passing species predominates for both elements by a factor of 10 and 2-3 for Pt and Rh, respectively, evidencing that particulate species coexist with truly dissolved forms. Temporal variations were observed for Pt, as opposed to Rh. These findings contribute to the gap in knowledge regarding Pt and Rh mobility in aquatic systems.

6.
Cytokine ; 125: 154791, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401369

RESUMO

BACKGROUND AND AIM: Chemotherapy drugs that act via Toll-like receptors (TLRs) can exacerbate mucosal injury through the production of cytokines. Intestinal mucositis can activate TLR2 and TLR4, resulting in the activation of NF-κB. Intestinal mucositis characterized by intense inflammation is the main side effect associated with 5-fluorouracil (5-FU) treatment. Saccharomyces boulardii CNCM I-745 (S.b) is a probiotic yeast used in the treatment of gastrointestinal disorders. The main objective of the study was to evaluate the effect of S.b treatment on the Toll-like/MyD88/NF-κB/MAPK pathway activated during intestinal mucositis and in Caco-2 cells treated with 5-FU. METHODS: The mice were divided into three groups: saline (control), saline + 5-FU, and 5-FU + S.b (1.6 × 1010 colony forming units/kg). After 3 days of S.b administration by gavage, the mice were euthanized and the jejunum and ileum were removed. In vitro, Caco2 cells were treated with 5-FU (1 mM) alone or in the presence of lipopolysaccharide (1 ng/ml). When indicated, cells were exposed to S.b. The jejunum/ileum samples and Caco2 cells were examined for the expression or concentration of the inflammatory components. RESULTS: Treatment with S.b modulated the expressions of TLR2, TLR4, MyD88, NF-κB, ERK1/2, phospho-p38, phospho-JNK, TNF-α, IL-1ß, and CXCL-1 in the jejunum/ileum and Caco2 cells following treatment with 5-FU. CONCLUSION: Toll-like/MyD88/NF-κB/MAPK pathway are activated during intestinal mucositis and their modulation by S.b suggests a novel and valuable therapeutic strategy for intestinal inflammation.


Assuntos
Citocinas/metabolismo , Fluoruracila/farmacologia , Mucosite/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Probióticos/farmacologia , Saccharomyces boulardii/metabolismo , Receptores Toll-Like/metabolismo , Animais , Células CACO-2 , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Citocinas/genética , Fluoruracila/efeitos adversos , Humanos , Íleo/metabolismo , Imuno-Histoquímica , Inflamação/metabolismo , Interleucina-1beta/genética , Janus Quinases/metabolismo , Jejuno/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Mucosite/tratamento farmacológico , Fosforilação , Probióticos/administração & dosagem , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptores Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Talanta ; 175: 1-8, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28841964

RESUMO

The determination of Platinum-group elements (PGE) in relevant environmental matrices is a challenging task. Sensitive and accurate analytical procedures for simultaneous determination of Pt and Rh are still needed. In this study, we report for the first time on the use of second derivative signal transformation to the ultra-trace simultaneous determination of Pt and Rh by Adsorptive Cathodic Stripping Voltammetry (AdCSV). With that step, the ill-defined peaks typically observed in the original voltammograms are transformed into well-shaped peaks, resulting in accurate detection. The experimental conditions were investigated and optimised: a suitable electrolyte for both elements, with less reagents consumption, (0.25M H2SO4, 0.05M HCl, 0.01M FA and 0.5mM HZ), deposition time (td) and deposition potential (Ed). For td = 120s and Ed = -0.75V, linear relationships r > 0.999 were obtained in the concentration range up to 5.8ngL-1 (27 pM) for Pt and up to 3.4ngL-1 (34 pM) for Rh. Limits of detection were 0.2ngL-1 for Pt and 0.08ngL-1 for Rh. Lower values can be achieved by increasing the deposition time. Limits of quantification, LOQ, calculated as 3 times LOD, were 0.5ngL-1 for Pt and 0.2ngL-1 for Rh. The sensitivity of Pt was affected by elevated Zn concentrations, whereas a minor effect was observed for Rh. However, Pt and Rh determinations were not influenced using the standard addition method. Precision as intermediate precision and expressed as relative standard deviation, based on Pt and Rh spiked solutions and digested road dust CRM BCR-723 was 17% and 20% for Pt and Rh, respectively. Recoveries of CRM were around 90% for both elements. The method was successfully applied in the simultaneous determination of Pt and Rh in sediments from Tagus estuary and, for the first time, dissolved Rh was determined in water samples of a waste water treatment plant. Application of this technique in a multidisciplinary approach will be a relevant contribution to the current understanding of PGE cycle and fate in the environment.

8.
BMC Complement Altern Med ; 15: 208, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26134625

RESUMO

BACKGROUND: Plants rich in flavonoids, such as açaí (Euterpe oleraceae Mart.), can induce antinociception in experimental animals. Here, we tested an extract obtained from the stones of açaí fruits (açaí stone extract, ASE), a native plant from the Amazon region of Brazil, in models of acute/inflammatory and chronic pain. METHODS: Antinociceptive effects of ASE were evaluated in the hot plate, formalin, acetic acid writhing, carrageenan, and neuropathic pain models, as well as in thermal hyperalgesia and mechanical allodynia models induced by spinal nerve ligation. Antinociceptive activities were modulated by the administration of cholinergic, adrenergic, opioid, and L-arginine-NO antagonists. RESULTS: Oral administration of ASE (30, 100, or 300 mg.kg(-1)) dose-dependently reduced nociceptive responses to acute/inflammatory pain in mice, including thermal hyperalgesia, acetic acid-induced writhing, and carrageenan-induced thermal hyperalgesia. Moreover, ASE reduced the neurogenic and inflammatory phases after intraplantar injection of formalin in mice. The antinociceptive effect of ASE (100 mg · kg(-1)) in a hot plate protocol, was inhibited by pre-treatment with naloxone (1 mg · kg(-1)), atropine (2 mg · kg(-1)), yohimbine (5 mg · kg(-1)), or L-NAME (30 mg · kg(-1)). Furthermore, ASE prevented chronic pain in a rat spinal nerve ligation model, including thermal hyperalgesia and mechanical allodynia. CONCLUSION: ASE showed significant antinociceptive effect via a multifactorial mechanism of action, indicating that the extract may be useful in the development of new analgesic drugs.


Assuntos
Analgésicos , Euterpe/química , Neuralgia/tratamento farmacológico , Extratos Vegetais , Analgésicos/química , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos
9.
Sci Total Environ ; 488-489: 316-24, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24836387

RESUMO

Determining the environmental risk of nanoparticles (NPs) requires an in-depth understanding of the NP core, the particle surface coatings and the interactions of the two with environmental matrices. Non-coated ZnO NPs (nZnO) are known to release ionic Zn, contributing directly to the toxicity of these particles. On the other hand, relatively less data are available for particles that have coatings designed to increase particle stability. In this study, Chlamydomonas reinhardtii was exposed to either a soluble Zn salt or nZnO with different stabilizers: (i) bare nZnO, (ii) polyacrylic acid-stabilized, nZnO-PAA, or a (iii) sodium hexametaphosphate-stabilized, nZnO-HMP. Multiple techniques were used to quantify particle agglomeration and dissolution. The dissolution of the NPs depended on the stabilizer, with the largest dissolution obtained for the bare nZnO (near total dissolution), followed by the nZnO-PAA. When exposed to the bare and PAA-stabilized nZnOs, bioaccumulation was largely accounted for by free Zn. On the other hand, the bioaccumulation of nZnO-HMP was greater than could be attributed to the release of free Zn from the particles. The increased Zn bioaccumulation was hypothesized to have resulted from the biological stimulation of C. reinhardtii due to phosphate from the particle coating.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Chlamydomonas reinhardtii/metabolismo , Nanopartículas/metabolismo , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/metabolismo
10.
Curr Top Med Chem ; 12(19): 2037-48, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23167793

RESUMO

Diabetes is a metabolic disorder characterized by hyperglycemia. When not properly controlled, complications include neuropathy, coronary artery disease, and renal failure. Several drugs are approved for diabetes treatment; however their use is associated with side effects and lack of efficacy in attenuating the development of long-term complications. This work describes the virtual screening and synthesis of a novel series of sulfonylhydrazone derivatives designed as peroxisome proliferator-activated receptor gamma (PPARγ) agonists and investigation of the analogs for hypoglycemic activity in a murine model of diabetes. Docking studies identified LASSBio-331 (5) as having theoretical affinity for PPARγ similar to the prototype (S)-rosiglitazone. Several structural modifications were proposed for the structure of LASSBio-331, resulting in the synthesis of five novel compounds, which showed experimental affinity for PPARγ. Among these new compounds, LASSBio-1471 (15) had the best theoretical binding energy for PPARγ and was selected for testing in STZ-induced diabetes. Four weeks after single intravenous injection of STZ (60 mg/kg), Wistar rats were treated with vehicle (DMSO) or LASSBio-1471 (20 mg/kg, i.p.) for 7 days. The blood glucose levels of rats treated with LASSBio-1471 were reduced from 548.4 ± 26.0 mg/dL before treatment to 259.6 ± 73.1 mg/dL (P < 0.05). Paw withdrawal threshold was significantly reduced in diabetic rats and was restored from 21.9 ± 1.7 g to 36.7 ± 1.2 g after 7 days of treatment with LASSBio-1471 (P < 0.05). Thus, the novel sulfonylhydrazone derivative is a PPARγ ligand that is effective for treatment of diabetic neuropathy in STZ-injected rats.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hidrazonas/farmacologia , Hipoglicemiantes/farmacologia , PPAR gama/agonistas , Animais , Teste de Tolerância a Glucose , Hidrazonas/síntese química , Hidrazonas/uso terapêutico , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estreptozocina , Termodinâmica
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