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1.
Part Fibre Toxicol ; 17(1): 55, 2020 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-33099312

RESUMO

BACKGROUND: Plastic is everywhere. It is used in food packaging, storage containers, electronics, furniture, clothing, and common single-use disposable items. Microplastic and nanoplastic particulates are formed from bulk fragmentation and disintegration of plastic pollution. Plastic particulates have recently been detected in indoor air and remote atmospheric fallout. Due to their small size, microplastic and nanoplastic particulate in the atmosphere can be inhaled and may pose a risk for human health, specifically in susceptible populations. When inhaled, nanosized particles have been shown to translocate across pulmonary cell barriers to secondary organs, including the placenta. However, the potential for maternal-to-fetal translocation of nanosized-plastic particles and the impact of nanoplastic deposition or accumulation on fetal health remain unknown. In this study we investigated whether nanopolystyrene particles can cross the placental barrier and deposit in fetal tissues after maternal pulmonary exposure. RESULTS: Pregnant Sprague Dawley rats were exposed to 20 nm rhodamine-labeled nanopolystyrene beads (2.64 × 1014 particles) via intratracheal instillation on gestational day (GD) 19. Twenty-four hours later on GD 20, maternal and fetal tissues were evaluated using fluorescent optical imaging. Fetal tissues were fixed for particle visualization with hyperspectral microscopy. Using isolated placental perfusion, a known concentration of nanopolystyrene was injected into the uterine artery. Maternal and fetal effluents were collected for 180 min and assessed for polystyrene particle concentration. Twenty-four hours after maternal exposure, fetal and placental weights were significantly lower (7 and 8%, respectively) compared with controls. Nanopolystyrene particles were detected in the maternal lung, heart, and spleen. Polystyrene nanoparticles were also observed in the placenta, fetal liver, lungs, heart, kidney, and brain suggesting maternal lung-to-fetal tissue nanoparticle translocation in late stage pregnancy. CONCLUSION: These studies confirm that maternal pulmonary exposure to nanopolystyrene results in the translocation of plastic particles to placental and fetal tissues and renders the fetoplacental unit vulnerable to adverse effects. These data are vital to the understanding of plastic particulate toxicology and the developmental origins of health and disease.


Assuntos
Poliestirenos/toxicidade , Animais , Feminino , Feto , Humanos , Exposição por Inalação , Exposição Materna , Troca Materno-Fetal , Tamanho da Partícula , Placenta , Plásticos , Poliestirenos/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley
2.
Physiol Genomics ; 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32956022

RESUMO

Our goal was to elucidate microRNAs (miRNAs) that may repress the excess bone morphogenetic protein (BMP) signaling observed during pathological calcification in the Klotho mouse model of kidney disease. We hypothesized that restoring healthy levels of miRNAs that post-transcriptionally repress osteogenic calcific factors may decrease aortic calcification. Our relative abundance profiles of miRNAs in healthy aorta differ greatly from those in calcified mouse aorta. Many of these miRNAs are predicted to regulate proteins involved in BMP signaling and may control osteogenesis. Two differentially regulated miRNAs, miR-145 and miR-378, were selected based on three criteria: reduced levels in calcified aorta, the ability to target more than one protein in the BMP signaling pathway, and conservation of targeted sequences between humans and mice. Forced expression using a lentiviral vector demonstrated that restoring normal levels repressed the synthesis of BMP2 and other pro-osteogenic proteins and inhibited pathological aortic calcification in Klotho mice with renal insufficiency. This study identified miRNAs that may impact BMP signaling in both sexes and demonstrated the efficacy of selected miRNAs in reducing aortic calcification in vivo. Calcification of the aorta and the aortic valve resulting from abnormal osteogenesis is common in those with kidney disease, diabetes, and high cholesterol. Such vascular osteogenesis is a clinically significant feature. The calcification modulating miRNAs described here are candidates for biomarkers and "miRNA replacement therapies" in the context of chronic kidney disease and other pro-calcific conditions.

3.
Food Res Int ; 106: 90-97, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29580002

RESUMO

This study aims to use ice nucleation proteins (INPs) as a novel approach to improve the efficiency of freeze drying process and investigate the related mechanism of ice morphology. Our results show that INPs can significantly improve freeze drying efficiency with increased primary drying rate under the increase of INP concentration from 0 to 10-2mg/mL. Moreover, such improvement was more significant at higher subzero freezing temperatures with the addition of INPs, when the control samples were unable to freeze. Those improvements further lead to reduced total drying time, which suggests an estimated total energy saving of 28.5% by INPs. Our ice morphology results indicate the ability of INPs to alter ice morphology with lamellar ice structure and larger crystal size, which both show linear relationships with primary drying rate. The results further suggest that these ice morphology characteristics induced by INPs are very likely to facilitate the water vapor flow and improve the sublimation rate. Additionally, the increase of freeze drying efficiency can also be achieved by INPs in other food systems like coffee and milk with elevated primary drying rate. The results of this study suggest great potential of using INPs to improve the efficiency of freeze drying process for a wide range of food products and other related applications. This study also provides new insights into the relationship between process efficiency and ice morphology.


Assuntos
Proteínas da Membrana Bacteriana Externa , Dessecação , Manipulação de Alimentos/métodos , Liofilização/métodos , Congelamento , Gelo/análise , Água/química , Animais , Café , Eficiência , Humanos , Leite , Vapor
4.
J Agric Food Chem ; 65(11): 2373-2382, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28241114

RESUMO

Freeze concentration is a separation process with high success in product quality. The remaining challenge is to achieve high efficiency with low cost. This study aims to evaluate the potential of using ice nucleation proteins (INPs) as an effective method to improve the efficiency of block freeze concentration while also exploring the related mechanism of ice morphology. Our results show that INPs are able to significantly improve the efficiency of block freeze concentration in a desalination model. Using this experimental system, we estimate that approximately 50% of the energy cost can be saved by the inclusion of INPs in desalination cycles while still meeting the EPA standard of drinking water (<500 ppm). Our investigative tools for ice morphology include optical microscopy and X-ray computed tomography imaging analysis. Their use indicates that INPs promote the development of a lamellar structured ice matrix with larger hydraulic diameters, which facilitates brine drainage and contains less brine entrapment as compared to control samples. These results suggest great potential for applying INPs to develop an energy-saving freeze concentration method via the alteration of ice morphology.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Congelamento , Gelo/análise , Água/química
5.
Mol Cancer Ther ; 8(11): 3151-61, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19887542

RESUMO

There is increasing evidence that tumor-associated macrophages promote the malignancy of some cancers. Colony-stimulating factor-1 (CSF-1) is expressed by many tumors and is a growth factor for macrophages and mediates osteoclast differentiation. Herein, we report the efficacy of a novel orally active CSF-1 receptor (CSF-1R) kinase inhibitor, JNJ-28312141, in proof of concept studies of solid tumor growth and tumor-induced bone erosion. H460 lung adenocarcinoma cells did not express CSF-1R and were not growth inhibited by JNJ-28312141 in vitro. Nevertheless, daily p.o. administration of JNJ-28312141 caused dose-dependent suppression of H460 tumor growth in nude mice that correlated with marked reductions in F4/80(+) tumor-associated macrophages and with increased plasma CSF-1, a possible biomarker of CSF-1R inhibition. Furthermore, the tumor microvasculature was reduced in JNJ-28312141-treated mice, consistent with a role for macrophages in tumor angiogenesis. In separate studies, JNJ-28312141 was compared with zoledronate in a model in which MRMT-1 mammary carcinoma cells inoculated into the tibias of rats led to severe cortical and trabecular bone lesions. Both agents reduced tumor growth and preserved bone. However, JNJ-28312141 reduced the number of tumor-associated osteoclasts superior to zoledronate. JNJ-28312141 exhibited additional activity against FMS-related receptor tyrosine kinase-3 (FLT3). To more fully define the therapeutic potential of this new agent, JNJ-28312141 was evaluated in a FLT3-dependent acute myeloid leukemia tumor xenograft model and caused tumor regression. In summary, this novel CSF-1R/FLT3 inhibitor represents a new agent with potential therapeutic activity in acute myeloid leukemia and in settings where CSF-1-dependent macrophages and osteoclasts contribute to tumor growth and skeletal events.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Imidazóis/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Nus , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Ratos , Ratos Sprague-Dawley , Receptor de Fator Estimulador de Colônias de Macrófagos/sangue , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Especificidade por Substrato , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/metabolismo
6.
Bioorg Med Chem Lett ; 18(6): 2097-102, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18289848

RESUMO

A series of 3,4,6-substituted 2-quinolones has been synthesized and evaluated as inhibitors of the kinase domain of macrophage colony-stimulating factor-1 receptor (FMS). The fully optimized compound, 4-(4-ethyl-phenyl)-3-(2-methyl-3H-imidazol-4-yl)-2-quinolone-6-carbonitrile 21b, has an IC(50) of 2.5 nM in an in vitro assay and 5.0 nM in a bone marrow-derived macrophage cellular assay. Inhibition of FMS signaling in vivo was also demonstrated in a mouse pharmacodynamic model.


Assuntos
Macrófagos/efeitos dos fármacos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Quinolonas/síntese química , Quinolonas/farmacologia , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Proliferação de Células/efeitos dos fármacos , Polarização de Fluorescência , Genes fos/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Quinolonas/farmacocinética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/metabolismo , Relação Estrutura-Atividade
7.
Clin Diagn Lab Immunol ; 10(6): 1029-36, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14607863

RESUMO

Whether persons with multiple chemical sensitivity syndrome (MCS) have immunological abnormalities is unknown. To assess the reliability of selected immunological tests that have been hypothesized to be associated with MCS, replicate blood samples from 19 healthy volunteers, 15 persons diagnosed with MCS, and 11 persons diagnosed with autoimmune disease were analyzed in five laboratories for expression of four T-cell surface activation markers (CD25, CD26, CD38, and HLA-DR) and in four laboratories for autoantibodies (to smooth muscle, thyroid antigens, and myelin). For T-cell activation markers, the intralaboratory reproducibility was very good, with 90% of the replicates analyzed in the same laboratory differing by < or = 3%. Interlaboratory differences were statistically significant for all T-cell subsets except CD4+ cells, ranging from minor to eightfold for CD25+ subsets. Within laboratories, the date of analysis was significantly associated with the values for all cellular activation markers. Although reproducibility of autoantibodies could not be precisely assessed due to the rarity of abnormal results, there were inconsistencies across laboratories. The effect of shipping on all measurements, while sometimes statistically significant, was very small. These results support the reliability of fresh and shipped samples for detecting large (but perhaps not small) differences between groups of donors in the T-cell subsets tested. When comparing markers that are not well standardized, it may be important to distribute samples from different study groups evenly over time.


Assuntos
Testes Imunológicos/normas , Sensibilidade Química Múltipla/diagnóstico , Antígenos de Diferenciação de Linfócitos T/sangue , Autoanticorpos/sangue , Doenças Autoimunes/diagnóstico , Estudos de Casos e Controles , Humanos , Testes Imunológicos/métodos , Ativação Linfocitária , Variações Dependentes do Observador , Reprodutibilidade dos Testes
8.
Environ Pollut ; 117(1): 1-3, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11843525

RESUMO

Hexavalent chromium [Cr(VI)] in the form of potassium dichromate was photochemically reduced to trivalent chromium [Cr(III)] in aqueous solutions containing glycerol. This reaction occurred rapidly during irradiation with either unfiltered sunlight or a UVA-emitting light source. Photochemical reduction of Cr(VI) was pH-dependent and did not occur in dilute solutions of sodium hydroxide. In acidified solutions, the reduction occurred at elevated rates and at lower concentrations of glycerol. This reaction was found to be dependent on the unsubstituted alcohol groups of glycerol since alpha-phosphoglycerol and beta-phosphoglycerol did not support the photochemical reduction of Cr(VI). These findings suggest that glycerol or related polyols can be used for the remediation of hexavalent (toxic) chromium at contaminated environmental sites.


Assuntos
Carcinógenos Ambientais/química , Cromo/química , Glicerol/química , Resíduos Perigosos , Oxirredução , Fotoquímica , Soluções
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