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1.
ACS Appl Bio Mater ; 4(12): 8477-8486, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-35005943

RESUMO

Recently, various types of nanomaterials have been employed to design delivery vehicles for curcumin to address the problems of poor bioavailability, low aqueous solubility, and rapid metabolism. The present study focuses on a direct one-pot synthesis of curcumin-derived nanoparticles and exploits their potential therapeutic properties in cancer cells in vitro without additional delivery vehicles. The nanoparticles, named E-Curc-dots, are synthesized using three precursor molecules, ethylenediamine (EDA), curcumin, and citric acid. The structure, composition, and physichemical properties of the nanodots are characterized and identified by employing spectroscopic and microscopic techniques. The as-synthesized E-Curc-dots exhibit bright blue photoluminescence due to the incorporation of nitrogen from the EDA precursor molecule. The characterization studies show a uniform distribution of dots with an average size of 4.6 ± 1.7 nm and, notably, that the dots retain some of the major characteristics of native curcumin with much improved water solubility and bioavailability. The E-Curc-dots show antioxidation activity at low concentrations (<0.08 mg/mL) with low levels of reactive oxygen species (ROS) generation, i.e., 82% of the ROS level in cells without treatment for A549 cells; however, at high concentrations, the nanodots exhibit a pro-oxidant effect on both the cancer cells (A549) and normal cells (EA.hy926) by inducing more ROS generation and dose-dependent cytotoxicity. The E-Curc-dots demonstrate higher cytotoxicity toward cancer cells compared to native curcumin at a lower concentration. The results indicate the efficacy of E-Curc-dots as an antiproliferative and ROS regulator with the ability of cellular bioimaging.


Assuntos
Curcumina , Nanopartículas , Antioxidantes/farmacologia , Curcumina/farmacologia , Espécies Reativas de Oxigênio
2.
Int J Nanomedicine ; 15: 8281-8292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149575

RESUMO

BACKGROUND: The application of silver nanoparticles (AgNPs) is growing exponentially, and its potential damage to the cardiac remains to be elucidated. The purpose of this study was to investigate the ameliorative effect of sodium selenite on silver nanoparticles-induced myocardiocyte structural alterations in rats. MATERIALS AND METHODS: Forty male Sprague-Dawley (SD) rats were randomly divided into four groups: control group, AgNPs group, Se control group, and AgNPs + Se group. SD rats were administered AgNPs through a single intratracheal instillation, and sodium selenite was given by intraperitoneal injection for seven days. Cardiac function was determined by echocardiography and hemodynamic, ultrastructural changes by transmission electron microscopy examination. Mitochondrial fission and autophagy markers were measured by Western blotting. RESULTS: AgNPs caused a significant decrease in cardiac contraction, diastolic dysfunction, fragmentation, and lysis of the myofibrils, the formation of stenosis in the capillary, damaging the mitochondria membrane and cristae. AgNPs significantly increased mitochondrial fission markers dynamin-related protein 1 (Drp1), phospho-Drp1 (p-Drp1), and mitochondrial fission protein 1 (Fis1), as well as autophagy marker LC3 II/I (P<0.05). Treatment with sodium selenite is capable of protecting cardiac function from AgNPs toxicity through attenuating ultrastructural alterations, stabilizing mitochondrial dynamic balance and blocking mitochondrial autophagy. CONCLUSION: We conclude that the protection of sodium selenite against silver nanoparticles-induced myocardiocyte structural alterations is associated with stabilizing mitochondrial dynamic balance and mitophagy.


Assuntos
Cardiomiopatias/induzido quimicamente , Cardiotônicos/farmacologia , Nanopartículas Metálicas/efeitos adversos , Selenito de Sódio/farmacologia , Animais , Autofagia , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Morte Celular/efeitos dos fármacos , Dinaminas/metabolismo , Eletrocardiografia , Masculino , Nanopartículas Metálicas/química , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Mitofagia/efeitos dos fármacos , Miocárdio/ultraestrutura , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Prata/efeitos adversos , Prata/química
3.
Int J Nanomedicine ; 15: 633-645, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099356

RESUMO

BACKGROUND: With the increased application of Silver nanoparticles (AgNP), its potential concerns to the health of human beings remain to be defined. This study aims to explore the harmful effects of AgNP on lung tissue in animals and to examine the mechanisms of protection achieved by sodium selenite. METHODS: Sprague-Dawley(SD) rats were exposed to AgNP (200 µL,1mg/mL) through a single intratracheal instillation. Sodium selenite (0.2mg/kg) was i.p. injected. Malondialdehyde (MDA) and glutathione (GSH) were measured using a spectrophotometer. Histological outcomes and ultrastructural changes were assessed by hematoxylin and eosin (HE) staining and electronic microscopy. Caspases and mitochondrial fission and fusion markers were measured by Western blotting. RESULTS: The histopathologic findings showed that AgNP significantly increased the thickness of alveolar septa, accumulation of macrophage, and the formation of pulmonary bullae and pulmonary consolidation. Ultrastructural studies showed localization of AgNP inside the mitochondria, hyperplasia and vacuolation of type I and type II alveolar cells, lysis of osmiophilic lamellar bodies, and swollen of the mitochondria. AgNP elevated MDA and reduced GSH levels. AgNP activated caspases-3, increased mitochondrial fission markers Dynamin-related protein 1 (Drp1) and phospho-Drp1(p-Drp1), and decreased fusion proteins optic atrophy 1 (Opa1) and mitofusins 2 (Mfn2). Treatment with sodium selenite for 7 days corrected the AgNP-caused alterations in morphological, ultrastructural, oxidative stress, caspase-3 activation and mitochondrial dynamic imbalance. CONCLUSION: We conclude that the exposure of AgNP causes lung tissue damage by enhances oxidative stress, activates caspases-3, and triggers mitochondrial dynamic imbalance towards fission. Sodium selenite effectively detoxifies the AgNP-induced damage to the lung tissue by preventing the above alterations.


Assuntos
Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Dinâmica Mitocondrial/efeitos dos fármacos , Prata/efeitos adversos , Selenito de Sódio/farmacologia , Animais , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Dinaminas/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Glutationa/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Malondialdeído/metabolismo , Nanopartículas Metálicas/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Prata/química
4.
J Biophotonics ; 13(1): e201900224, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568652

RESUMO

Dental caries usually occurs at interproximal and occlusal surfaces. The purpose of the present study was to determine if characteristic spectral factors extracted from autofluorescence (AF) spectra are informative regarding caries detection and the determination of caries stage as compared with DIAGNOdent results. AF spectra were obtained from caries lesions of different severities at two locations using a 405 nm laser. Three spectral factors, that is, spectral slope at 550 to 600 nm, spectral area under the curve at 500 to 590 nm and two-peak ratio between 625 and 667 nm, were extracted. The values of three spectral factors linearly decreased as caries progressed. According to micro-CT images, conventional visual and tactile inspections of lesions under or overestimated (25%-65%) caries states, and brown or thickly stained layer on interproximal or occlusal surfaces, respectively, caused misclassifications of caries stage. Of the spectral factors examined, spectral slope and area under curve for interproximal and occlusal surfaces, respectively, were found to be significantly related to caries stage and showed least data overlap. For interproximal and occlusal surfaces, DIAGNOdent readings of different stages overlapped considerably though their mean values were significantly different regardless of stage.


Assuntos
Cárie Dentária , Cárie Dentária/diagnóstico por imagem , Suscetibilidade à Cárie Dentária , Fluorescência , Humanos , Lasers , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Microtomografia por Raio-X
5.
Water Environ Res ; 91(3): 198-207, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30710401

RESUMO

Herein, we report the comparison of two different mixing methods for reductive dechlorination of gamma-hexachlorocyclohexane (γ-HCH), aldrin, and p, p'-dichlorodiphenyl-trichloroethane (p, p'-DDT), using iron/palladium (Fe/Pd) bimetallic nanoparticles. A noticeable enhancement of the reaction rate was found when the reductive dechlorination reaction was carried out in an ultrasound bath as compared with a platform shaker. These enhancements could be attributed to (a) the continuous cleaning and chemical activation of the surfaces of nanoscale Fe/Pd bimetallic nanoparticles by the combined chemical and physical effects of acoustic cavitation; and (b) the accelerated mass transport rates of target POPs to the surfaces of the Fe/Pd nanoparticles. Finally, the degradation intermediates and final products were determined by gas chromatography/mass spectrometry (GC/MS) analysis and the plausible degradation pathways for γ-HCH, aldrin, and p, p'-DDT by Fe/Pd bimetallic nanoparticles were proposed. PRACTITIONER POINTS: Exposure to POPs is a resilient global environmental and health issue. Fe/Pd bimetallic nanoparticles demonstrated > 90 % removal of POPs in the first 30 minutes of the reaction via ultrasonic mixing. GC-MS analyses provided verification of POPs degradation intermediates and final products.


Assuntos
Halogenação , Ferro/química , Nanopartículas Metálicas/química , Compostos Orgânicos/química , Paládio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Aldrina/química , DDT/química , Hexaclorocicloexano/química , Oxirredução , Sonicação
6.
J Nanosci Nanotechnol ; 19(4): 2193-2197, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486966

RESUMO

In this study, a geopolymer having a nano-scaled structure was fabricated using recycling fly ash slag discharged from IGCC (Integrated Gasification Combined Cycle), to assess the possibility of employing it to replace high strength concrete. Strength, density, crystal phase, and bonding structure, were measured and the nano-size crystal phase of the geopolymers was observed as a function of experimental parameters such as water-to-solid ratio (w/s ratio), flow of paste, and amount of sodium silicate in the alkali activator, NaOH. The geopolymer prepared with NaOH containing 50~70% sodium silicate and a w/s ratio of 0.26~0.28 showed a compressive strength of 75~80 MPa, which satisfied the design standard for high strength concrete in Korea, 40 MPa. The specimen made with NaOH containing 55% sodium silicate had plate-shaped crystals with a nanoscale size, 100 nm or less, and showed compressive strength of 77 MPa, 3.9 times higher than that made with only NaOH. From the viewpoint of microstructure, it was confirmed that nano-sized plate-like crystals and amorphous structure were both effective in improving the strength of the specimen. In conclusion, this study showed that high-strength geopolymer made from IGCC coal ash slag may replace cement used in building materials and concrete secondary products in the near future.

7.
Redox Biol ; 15: 327-334, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29306790

RESUMO

Exposure to (bi)sulfite (HSO3-) and sulfite (SO32-) has been shown to induce a wide range of adverse reactions in sensitive individuals. Studies have shown that peroxidase-catalyzed oxidation of (bi)sulfite leads to formation of several reactive free radicals, such as sulfur trioxide anion (.SO3-), peroxymonosulfate (-O3SOO.), and especially the sulfate (SO4. -) anion radicals. One such peroxidase in neutrophils is myeloperoxidase (MPO), which has been shown to form protein radicals. Although formation of (bi)sulfite-derived protein radicals is documented in isolated neutrophils, its involvement and role in in vivo inflammatory processes, has not been demonstrated. Therefore, we aimed to investigate (bi)sulfite-derived protein radical formation and its mechanism in LPS aerosol-challenged mice, a model of non-atopic asthma. Using immuno-spin trapping to detect protein radical formation, we show that, in the presence of (bi)sulfite, neutrophils present in bronchoalveolar lavage and in the lung parenchyma exhibit, MPO-catalyzed oxidation of MPO to a protein radical. The absence of radical formation in LPS-challenged MPO- or NADPH oxidase-knockout mice indicates that sulfite-derived radical formation is dependent on both MPO and NADPH oxidase activity. In addition to its oxidation by the MPO-catalyzed pathway, (bi)sulfite is efficiently detoxified to sulfate by the sulfite oxidase (SOX) pathway, which forms sulfate in a two-electron oxidation reaction. Since SOX activity in rodents is much higher than in humans, to better model sulfite toxicity in humans, we induced SOX deficiency in mice by feeding them a low molybdenum diet with tungstate. We found that mice treated with the SOX deficiency diet prior to exposure to (bi)sulfite had much higher protein radical formation than mice with normal SOX activity. Altogether, these results demonstrate the role of MPO and NADPH oxidase in (bi)sulfite-derived protein radical formation and show the involvement of protein radicals in a mouse model of human lung disease.


Assuntos
Asma/metabolismo , Pneumopatias/metabolismo , Neutrófilos/metabolismo , Sulfitos/toxicidade , Animais , Asma/induzido quimicamente , Asma/patologia , Líquido da Lavagem Broncoalveolar/química , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/metabolismo , Humanos , Lipopolissacarídeos/toxicidade , Pneumopatias/induzido quimicamente , Pneumopatias/patologia , Camundongos , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Oxirredução/efeitos dos fármacos , Peroxidases/química , Peroxidases/metabolismo , Detecção de Spin , Sulfito Oxidase/metabolismo
8.
Sci Total Environ ; 621: 930-938, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29223911

RESUMO

Growth of informal electronic waste (e-waste) recycling sector is an emerging problem for India. The presence of halogenated compounds in e-wastes may result in the formation of persistent organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during recycling processes. We therefore investigated PCBs and PCDD/Fs in surface soils explicitly from the informal e-waste recycling sites and nearby open dumpsites of major metropolitan cities from four corners of India, viz., New Delhi (North), Kolkata (East), Mumbai (West) and Chennai (South). In the informal e-waste recycling sites, the range of Σ26PCBs (0.4-488ng/g) and Æ©PCDD/Fs (1.0-10.6ng/g) were higher than Æ©26PCBs (0.3-21ng/g) and Æ©PCDD/Fs (0.15-7.3ng/g) from open dumpsites. In the e-waste sites, Æ©PCDDs were found with increasing trend from Æ©TetraCDD to OctaCDD, whereas Æ©PCDFs showed a reverse trend. The dominance of PCDF congeners and maximum toxicity equivalents (TEQ) for both PCDDs (17pg TEQ/g) and PCDFs (82pg TEQ/g) at Mandoli in New Delhi has been related to intensive precious metal recovery process using acid bath. Among dumpsites, highest TEQ for PCDD/Fs was observed at Kodangaiyur dumpsite of Chennai (CNDS-02, 45pg TEQ/g). Positive Matrix Factorization (PMF) model identified distinct congener pattern based on the functional activities, such as e-waste dismantling, shredding, precious metal recovery and open burning in dumpsites. E-waste metal recovery factor was loaded with 86-91% of PCB-77, -105, -114, -118 and 30% of PCB-126, possibly associated with the burning of wires during the copper extraction process. Almost 70% of the Æ©26PCB concentrations was comprised of the dioxin-like PCB congeners with a maximum concentration of 437ng/g at New Moore market in Chennai, followed by Wire Lane (102ng/g), in Mumbai. We speculate that PCB-126 might have resulted from combustion of plastic materials in e-waste stream and dumped waste.


Assuntos
Dibenzofuranos Policlorados/análise , Resíduo Eletrônico , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Reciclagem , Poluentes do Solo/análise , Cidades , Monitoramento Ambiental , Índia , Medição de Risco , Solo
9.
Curr Microbiol ; 74(11): 1247-1252, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28913636

RESUMO

A Gram-stain-negative bacterial strain designated Con4T was isolated from activated sludge in a seawater treatment system. The strain was rod-shaped, motile, aerobic, and formed yellow-colored colonies on agar medium. Cells contained carotenoid pigments, but flexirubin-type pigments were absent. Based on 16S rRNA gene sequence analysis, the strain was assigned to the genus Gelidibacter. Optimum growth occurred at 20 °C, pH 7.0, and 1-2% (w/v) NaCl. Prominent fatty acid types were iso-C15:0, anteiso-C15:0, and iso-C16:0 3OH. Diphosphatidylglycerol and phosphatidylethanolamine were present as the major polar lipids. MK-6 was present as major menaquinone. Strain Con4T showed the highest sequence similarity with Gelidibacter mesophilus KCTC 12106T (96.5%), Gelidibacter gilvus IC158T (96.4%), and Gelidibacter algens ACAM 536T (95.8%). The G+C mol% contents of the strain Con4T were 37.7%. Distinct morphological, physiological, and genotypic differences from the previously described taxa support the classification of strain Con4T as a representative of a novel species in the genus Gelidibacter, for which the name Gelidibacter flavus sp. nov. is proposed. The type strain is Con4T (=KEMB 41-198T = JCM 31135T).


Assuntos
Flavobacteriaceae/classificação , Água do Mar/microbiologia , Esgotos/microbiologia , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Genoma Bacteriano , Genômica/métodos , Genótipo , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
10.
Environ Pollut ; 219: 998-1006, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27503054

RESUMO

River Brahmaputra (RB) from the outer Himalayan Range and River Hooghly (RH), a distributary of River Ganga, are the two largest transboundary perennial rivers supplying freshwater to the northeastern and eastern states of India. Given the history of extensive usage of organochlorine pesticides and increasing industrialization along the banks of these rivers we investigated selected organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the surface water of River Brahmaputra and River Hooghly. Geomean of ΣOCPs (53 ng L-1) and Σ19PCBs (108 ng L-1) was higher in RH compared with geomean of ΣOCPs (24 ng L-1) and Σ19PCBs (77 ng L-1) in RB. Among OCPs, γ-HCH showed maximum detection frequency in both the rivers reflecting ongoing lindane usage. DDT and endosulfan residues were observed at specific locations where past or ongoing sources exist. Elevated concentrations of heavier congeners (penta-hepta) were observed in those sites along RH where port and industrial activities were prevalent including informal electronic waste scrap processing units. Furthermore along River Hooghly PCB-126 was high in the suburban industrial belt of Howrah district. PCBs were found to be ubiquitously distributed in RB. Atmospheric transport of tri- and tetra-PCB congeners from the primary source regions might be a major contributor for PCBs in RB. Heavier congeners (penta-nona) in the urban centers of RB were likely due to industrial wastewater runoff from the oil refineries in the Brahmaputra valley. Σ19PCBs concentrations in this study exceeded the USEPA recommended limit for freshwater. Ecotoxicological risk assessment showed the possibility of adverse impact on the organisms in the lower trophic level due to DDT and lindane contamination. Impact of endosulfan on fishes might be of considerable concern for aquatic environment.


Assuntos
Baías/química , Ecotoxicologia , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Rios/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Índia , Medição de Risco
11.
Int J Syst Evol Microbiol ; 66(10): 3821-3827, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27381046

RESUMO

A novel Gram-stain-negative, coccus to oval-shaped, non-motile bacterium, designated strain S5T, was isolated from lagoon sediments collected from North Carolina, USA. Strain S5T was able to grow at 12-45 °C (optima, 30-37 °C) and at pH 6.3-9.0 (optima, 6.5-7.5). No added NaCl was required for growth of strain S5T. Strain S5T was positive for catalase and oxidase activity. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c and C16 : 0 were predominant fatty acids with minor amounts of C8 : 0 3-OH, C14 : 0, C16 : 0 3-OH, C18 : 1 2-OH, C14 : 1ω5c, C16 : 1ω5c and C19 : 0 cyclo ω8c. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified glycolipid were major polar lipids. Minor amounts of an unidentified amino lipid and three unidentified lipids were also detected. The G+C content of the genomic DNA was 73.5 mol%. 16S rRNA gene sequence comparisons indicated that strain S5T represents a member of the genus Roseomonas within the family Acetobacteraceae of the class Alphaproteobacteria. Strain S5T had a sequence similarity of 97.80 % with Roseomonas rhizosphaerae YW11T, 97.69 % with Roseomonas aestuarii JC17T and <97 % with other members of the genus Roseomonas. However, strain S5T showed only 45.2±2 and 17±2 % relatedness (based on DNA-DNA hybridization) with R. rhizosphaerae KACC 17225T (=YW11T) and R. aestuarii KCTC 22692T (=JC17T), respectively. Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of strain S5T as a representative of a novel species in the genus Roseomonas, for which the name Roseomonas rubra sp. nov. is proposed. The type strain is S5T (=KEMB 563-468T=JCM 31177T).


Assuntos
Sedimentos Geológicos/microbiologia , Methylobacteriaceae/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Methylobacteriaceae/genética , Methylobacteriaceae/isolamento & purificação , North Carolina , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Int J Syst Evol Microbiol ; 66(7): 2735-2739, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27117992

RESUMO

Strain S3T was isolated from lagoon sediments, and appeared as transparent colonies on agar plates, with cells staining Gram-negative. Catalase and oxidase were positive. S3T hydrolyzed starch, casein and tween-20, while urea, chitin, gelatin and tween-80 were not hydrolysed. C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c,C17 : 0 cyclo and C16 : 0 were the predominant fatty acids with minor amounts of C10 : 0 3-OH, C12 : 0, C14 : 0 and C16 : 0 2-OH. S3T contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) as major polar lipids with minor amounts of unidentified phospholipid (PL) and unidentified lipids (L1-2). Genomic DNA G+C content was 68.3 mol%. 16S rRNA gene sequence comparisons indicated that S3T represents a member of the genus Comamonas in family Comamonadaceae of the class Betaproteobacteria. S3T has a sequence similarity of 98.96 % with Comamonas koreensis YH12T, 97.93 % with Comamonas guangdongensis CY01T and <96.97 % with other members of the genus Comamonas. DNA-DNA hybridization values between S3T and the type strains of the most closely related species were clearly below the 70 % threshold. On the basis of phenotypic, genotypic and phylogenetic analysis, it is proposed that S3T represents a novel species of the genus Comamonas, for which the name Comamonas sediminis sp. nov. is proposed. The type strain is S3T (=KEMB 563-466T =JCM 31169T).


Assuntos
Comamonas/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Comamonas/genética , Comamonas/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , North Carolina , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Int J Biol Sci ; 11(8): 860-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26157341

RESUMO

Silver nanoparticles (AgNP), one of the most commonly used engineered nanomaterial for biomedical and industrial applications, has shown a toxic potential to our ecosystems and humans. In this study, murine hippocampal neuronal HT22 cells were used to delineate subcellular responses and mechanisms to AgNP by assessing the response levels of caspase-3, mitochondrial oxygen consumption, reactive oxygen species (ROS), and mitochondrial membrane potential in addition to cell viability testing. Selenium, an essential trace element that has been known to carry protecting property from heavy metals, was tested for its ameliorating potential in the cells exposed to AgNP. Results showed that AgNP reduced cell viability. The toxicity was associated with mitochondrial membrane depolarization, increased accumulation of ROS, elevated mitochondrial oxygen consumption, and caspase-3 activation. Treatment with sodium selenite reduced cell death, stabilized mitochondrial membrane potential and oxygen consumption rate, and prevented accumulation of ROS and activation of caspase-3. It is concluded that AgNP induces mitochondrial stress and treatment with selenite is capable of preventing the adverse effects of AgNP on the mitochondria.


Assuntos
Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Nanopartículas Metálicas , Mitocôndrias/efeitos dos fármacos , Prata/química , Selenito de Sódio/farmacologia , Animais , Linhagem Celular , Ativação Enzimática , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Consumo de Oxigênio , Espécies Reativas de Oxigênio/metabolismo
14.
Endocr Relat Cancer ; 22(2): R69-86, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25624167

RESUMO

Dietary ingestion of persistent organic pollutants (POPs) is correlated with the development of obesity. Obesity alters metabolism, induces an inflammatory tissue microenvironment, and is also linked to diabetes and breast cancer risk/promotion of the disease. However, no direct evidence exists with regard to the correlation among all three of these factors (POPs, obesity, and breast cancer). Herein, we present results from current correlative studies indicating a causal link between POP exposure through diet and their bioaccumulation in adipose tissue that promotes the development of obesity and ultimately influences breast cancer development and/or progression. Furthermore, as endocrine disruptors, POPs could interfere with hormonally responsive tissue functions causing dysregulation of hormone signaling and cell function. This review highlights the critical need for advanced in vitro and in vivo model systems to elucidate the complex relationship among obesity, POPs, and breast cancer, and, more importantly, to delineate their multifaceted molecular, cellular, and biochemical mechanisms. Comprehensive in vitro and in vivo studies directly testing the observed correlations as well as detailing their molecular mechanisms are vital to cancer research and, ultimately, public health.


Assuntos
Neoplasias da Mama/metabolismo , Poluentes Ambientais/toxicidade , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta , Exposição Ambiental , Feminino , Humanos
15.
Int J Syst Evol Microbiol ; 63(Pt 3): 1111-1118, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22729022

RESUMO

A Gram-stain-positive, non-motile, chemo-organotrophic, mesophilic, aerobic bacterium, designated A1(T), was isolated from sludge of a wastewater treatment plant. Strain A1(T) showed good ability to degrade ammonia and grew well on media amended with methanol and ammonia. Strain A1(T) grew with 0-11 % (w/v) NaCl, at 20-42 °C, but not <15 or >45 °C and at pH 6-10 (optimum pH 8.0-9.0). The isolate was catalase-positive and oxidase-negative. The DNA G+C content was 70.7 mol%. A comparative analysis of 16S rRNA gene sequences revealed that strain A1(T) formed a distinct phyletic lineage in the genus Brevibacterium and showed high sequence similarity with Brevibacterium casei NCDO 2048(T) (96.9 %), Brevibacterium celere KMM 3637(T) (96.9 %) and Brevibacterium sanguinis CF63(T) (96.4 %). DNA-DNA hybridization revealed <43 % DNA-DNA relatedness between the isolate and its closest phylogenetic relatives. The affiliation of strain A1(T) with the genus Brevibacterium was supported by the chemotaxonomic data: predominant quinone menaquinone MK-7(H2); polar lipid profile containing diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid; characteristic cell-wall diamino acid meso-diaminopimelic acid; whole-cell sugars galactose, xylose and ribose; absence of mycolic acids; and major fatty acids iso-C15 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The results of physiological and biochemical tests allowed phenotypic differentiation of strain A1(T) from members of the genus Brevibacterium. On the basis of the results in this study, a novel species, Brevibacterium ammoniilyticum sp. nov., is proposed. The type strain is A1(T) ( = KEMC 41-098(T)  = JCM 17537(T)  = KACC 15558(T)).


Assuntos
Amônia/metabolismo , Brevibacterium/classificação , Filogenia , Esgotos/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Brevibacterium/genética , Brevibacterium/isolamento & purificação , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Peptidoglicano/análise , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/análise , Águas Residuárias/microbiologia
16.
J Air Waste Manag Assoc ; 53(2): 227-36, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12617296

RESUMO

A thermophoretic precipitator (TP) that uses a novelty of direct sampling of ambient air particulate matter (PM) onto transmission electron microscopy (TEM) grids was designed and utilized to determine its potential applicability for the collection and consequent qualitative analyses of representative PM in the air, especially those with aerodynamic diameter less than 1 microm (PM1.0). After a calibration process, preliminary field tests were performed under different weather conditions, locations, and time frames. TEM, selected area electron diffraction (SAED), and electron energy-dispersive X-ray spectrometry (EDS) analyses were performed on individual samples, and chemical species were analyzed. During this investigation, individual air PM with different sizes ranging from 10 microm to 10 nm for TEM analysis was collected. Two observations were made: (1) a large fraction of collected particulates were aggregates of very small particles of both organic and inorganic origin, and (2) a large fraction of the collected particulates were crystalline or polycrystalline. This study has demonstrated, by utilization of SAED patterns from TEM on air particles collected by a TP, the potential to analyze and identify individual air PM in a nanometer regime qualitatively by combining SAED and EDS data.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Aerossóis , Microscopia Eletrônica , Tamanho da Partícula
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