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1.
Food Chem ; 343: 128511, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33168263

RESUMO

Inhibitors against cystine-glutamate antiporter, including erastin, elicit ferroptotic cell death. The erastin-induced ferroptotic cell death appears to be caused by cysteine as well as glutathione depletion. Cysteine is an essential substrate for sulfane sulfur producing systems in cells, generating persulfides that function as intracellular antioxidants and intermediates in iron-sulfur cluster production. Therefore, we examined whether botanical sulfane sulfur donors such as diallyl trisulfide (DATS) and dimethyl trisulfide (DMTS) prevent ferroptotic cell death in HT1080 cells treated with erastin. As a result, DMTS (20 µM) and DATS (10 µM) rescued the erastin-treated HT1080 cells by 69.6% and 91.6%, respectively. Furthermore, DMTS-containing squeeze of cabbage (2.0 g/L) and DATS-containing squeeze of garlic (0.07 g/L) rescued the erastin-treated HT1080 cells by 76.5% and almost 100%, respectively. In conclusion, the ingestion of trisulfides may bring about increased resistance to ferroptotic cell death in vivo.


Assuntos
Compostos Alílicos/farmacologia , Cisteína/metabolismo , Piperazinas/farmacologia , Extratos Vegetais/farmacologia , Sulfetos/farmacologia , Antioxidantes/farmacologia , Brassica/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cisteína/farmacologia , Ferroptose/efeitos dos fármacos , Alho/química , Glutationa/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Peróxidos Lipídicos/metabolismo , Extratos Vegetais/química , Sulfetos/metabolismo , Enxofre/farmacocinética
2.
Ecotoxicol Environ Saf ; 206: 111057, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32905911

RESUMO

The objective of this study was to explore potential microbial mechanisms associated with how water management may alter soil Cd availability under changing pe + pH environments. Four water regimes, aerobic [70% MWHC] + dissolved oxygen, aerobic, continuous flooding, and continuous flooding + N2, were applied to Cd-contaminated soil. The results show that the anoxic treatments were effective in decreasing soil pe + pH and in turn decreased Cd availability and increased soil S and Fe availability relative to those of the aerobic treatments. The decreased pe + pH enriched some anaerobic microorganisms such as those in the families Anaerolineaceae and Geobacteraceae. Conversely, other families, such as Gemmatimonadaceae and Sphingomonadaceae, appeared to be sensitive biomarkers that responded to aerobic treatments. Bacterial community structure and network interactions were altered to strengthen bacterial responses to different pe + pH environments as indicated by phylogenetic molecular ecological network (pMEN) analysis. The majority of predicted functional categories, such as metabolism, cell motility, and membrane transport, were affected by different irrigation regimes as indicated by a functional gene profile analysis. The categories were related to important traits that facilitated acclimation of bacteria to their local environment with altered soil pe + pH. Structural equation models revealed that soil pe + pH contributed significantly to soil enzyme activities and differences in bacterial community and function, and consequently, was responsible for the variation of soil Cd availability and iron or sulfur reduction.


Assuntos
Cádmio/farmacocinética , Microbiologia do Solo , Poluentes do Solo/farmacocinética , Solo/química , Irrigação Agrícola , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Cádmio/análise , Concentração de Íons de Hidrogênio , Ferro/análise , Ferro/farmacocinética , Oxirredução , Poluentes do Solo/análise , Enxofre/análise , Enxofre/farmacocinética
3.
J Mater Chem B ; 8(36): 8323-8336, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32793936

RESUMO

Exploiting two-dimensional nanomaterials as photo-based theranostic agents is promising for the highly efficient ablation of deep-tissue-buried tumors. However, they are limited by their poor absorption in the second near-infrared-light (NIR-II) bio-window (1000-1300 nm) and intrinsic nonbiodegradability. Herein, defect-rich sulfur-doped Ni(OH)2 (S-Ni(OH)2) nanosheets decorated with bovine serum albumin (BSA) as a novel theranostic agent is developed, which can accomplish multimodal-imaging-guided photothermal ablation of mouse cancers in the NIR-II bio-window. Sulfur doping extends the absorption spectra of Ni(OH)2 nanosheets from the visible to NIR-II bio-window, affording highly efficient photothermal conversion (58.20% for 1064 nm), entailing it to become an excellent contrast agent for photoacoustic imaging. Further, because of their intrinsic paramagnetic property, they can be applied for magnetic resonance imaging. Owing to the abundant defective sites in S-Ni(OH)2 nanosheets, they exhibit response to the tumor microenvironment, resulting in effective biodegradation and excretion from the body. In vivo toxicity experiments indicated that S-Ni(OH)2-BSA NSs delivered no appreciable toxicity and good biocompatibility. This work provides an avenue for the rational design of effective theranostics agents.


Assuntos
Antineoplásicos/uso terapêutico , Hidróxidos/uso terapêutico , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Níquel/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Bovinos , Feminino , Células HeLa , Humanos , Hidróxidos/química , Hidróxidos/farmacocinética , Hidróxidos/efeitos da radiação , Raios Infravermelhos , Camundongos Endogâmicos ICR , Imagem Multimodal , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Níquel/química , Níquel/farmacocinética , Níquel/efeitos da radiação , Terapia Fototérmica , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacocinética , Soroalbumina Bovina/uso terapêutico , Enxofre/química , Enxofre/farmacocinética , Enxofre/efeitos da radiação , Enxofre/uso terapêutico , Nanomedicina Teranóstica
4.
Environ Sci Pollut Res Int ; 26(20): 20866-20878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31111391

RESUMO

The establishment of phytoextraction crops on highly contaminated soils can be limited by metal toxicity. A recent proposal has suggested establishing support crops during the critical initial phase by metal immobilization through soil amendments followed by subsequent mobilization using elemental sulphur to enhance phytoextraction efficiency. This 'combined phytoremediation' approach is tested for the first time in a pot experiment with a highly contaminated soil. During a 14-week period, relatively metal-tolerant maize was grown in a greenhouse under immobilization (before sulphur (S) application) and mobilization (after S application) conditions with soil containing Cd, Pb and Zn contaminants. Apart from the control (C) sample, the soil was amended with activated carbon (AC), lignite (Lig) or vermicompost (VC) all in two different doses (dose 1~45 g additive kg-1 soil and dose 2~90 g additive kg-1 soil). Elemental S was added as a mobilization agent in these samples after 9 weeks. Biomass production, nutrient and metal bioavailability in the soil were determined, along with their uptake by plants and the resulting remediation factors. Before S application, Cd and Zn mobility was reduced in all the AC, Lig and VC treatments, while Pb mobility was increased only in the Lig1 and VC1 treatments. Upon sulphur application, Fe, Mn, Cd, Pb and Zn mobility was not significantly affected in the C, AC and VC treatments, nor total Cd, Pb and Zn contents in maize shoots. Increased sulphate, Mn, Cd, Pb and Zn mobilities in soil together with related higher total S, Mn, Pb and Zn contents in shoots were observed in investigated treatments in the last sampling period. The highest biomass production and the lowest metal toxicity were seen in the VC treatments. These results were associated with effective metal immobilization and showed the trend of steady release of some nutrients. The highest remediation factors and total elemental content in maize shoots were recorded in the VC treatments. This increased phytoremediation efficiency by 400% for Cd and by 100% for Zn compared to the control. Considering the extreme metal load of the soil, it might be interesting to use highly metal-tolerant plants in future research. Future investigations could also explore the effect of carbonaceous additives on S oxidation, focusing on the specific microorganisms and redox reactions in the soil. In addition, the homogeneous distribution of the S rate in the soil should be considered, as well as longer observation times.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metais Pesados/farmacocinética , Poluentes do Solo/farmacocinética , Enxofre , Zea mays/metabolismo , Biodegradação Ambiental , Disponibilidade Biológica , Biomassa , Carvão Vegetal/química , Compostagem , Metais Pesados/análise , Fósforo/farmacocinética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Solo/química , Poluentes do Solo/análise , Enxofre/farmacocinética , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento
5.
Environ Sci Pollut Res Int ; 25(24): 24338-24347, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948717

RESUMO

In this study, we investigated the effects of the arbuscular mycorrhizal fungi (AMF) Funneliformis mosseae and Diversispora spurcum on the growth, antioxidant physiology, and uptake of phosphorus (P), sulfur (S), lead (Pb), zinc (Zn), cadmium (Cd), and arsenic (As) by maize (Zea mays L.) grown in heavy metal-polluted soils though a potted plant experiment. F. mosseae significantly increased the plant chlorophyll a content, height, and biomass; decreased the H2O2 and malondialdehyde (MDA) contents; and enhanced the superoxide dismutase (SOD) and catalase (CAT) activities and the total antioxidant capacity (T-AOC) in maize leaves; this effect was not observed with D. spurcum. Both F. mosseae and D. spurcum promoted the retention of heavy metals in roots and increased the uptake of Pb, Zn, Cd, and As, and both fungi restricted heavy metal transfer, resulting in decreased Pb, Zn, and Cd contents in shoots. Therefore, the fungi reduced the translocation factors for heavy metal content (TF) and uptake (TF') in maize. Additionally, F. mosseae promoted P and S uptake by shoots, and D. spurcum increased P and S uptake by roots. Moreover, highly significant negative correlations were found between antioxidant capacity and the H2O2, MDA, and heavy metal contents, and there was a positive correlation with the biomass of maize leaves. These results suggested that AMF alleviated plant toxicity and that this effect was closely related to antioxidant activation in the maize leaves and increased retention of heavy metals in the roots.


Assuntos
Metais Pesados/farmacocinética , Micorrizas/fisiologia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Zea mays/microbiologia , Antioxidantes/metabolismo , Biomassa , Glomeromycota/fisiologia , Peróxido de Hidrogênio/metabolismo , Fósforo/farmacocinética , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/microbiologia , Poluentes do Solo/farmacocinética , Enxofre/farmacocinética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
6.
J Agric Food Chem ; 65(6): 1108-1115, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28128937

RESUMO

Acidification by oxidation of elemental sulfur (ES) can solubilize ZnO, providing slow release of both sulfur (S) and zinc (Zn) in soil. For this study, a new granular fertilizer with ES and ZnO was produced and evaluated. The effect of incorporating microorganisms or a carbon source in the granule was also evaluated. Four granulated ES-Zn fertilizers with and without S-oxidizing microorganisms, a commercial ES pastille, ZnSO4, and ZnO were applied to the center of Petri dishes containing two contrasting pH soils. Soil pH, CaCl2-extractable S and Zn, and remaining ES were evaluated at 30 and 60 days in two soil sections (0-5 and 5-9 mm from the fertilizer application site). A visualization test was performed to evaluate Zn diffusion over time. A significant pH decrease was observed in the acidic soil for all ES-Zn fertilizer treatments and in the alkaline soil for the Acidithiobacillus thiooxidans-inoculated treatment only. In agreement with Zn visualization tests, extractable-Zn concentrations were higher from the point of application in the acidic (62.9 mg dm-3) compared to the alkaline soil (5.5 mg dm-3). Elemental S oxidation was greater in the acidic soil (20.9%) than slightly alkaline soil (12%). The ES-Zn granular fertilizers increased S and Zn concentrations in soil and can provide a strategically slow release of nutrients to the soil.


Assuntos
Fertilizantes , Enxofre/farmacocinética , Zinco/farmacocinética , Acidithiobacillus thiooxidans/metabolismo , Aspergillus niger/metabolismo , Disponibilidade Biológica , Difusão , Concentração de Íons de Hidrogênio , Oxirredução , Solo/química , Microbiologia do Solo , Enxofre/metabolismo , Óxido de Zinco/química
7.
J Pharm Biomed Anal ; 131: 256-262, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27611097

RESUMO

There is increasing interest in the treatment of advanced stage ovarian cancer (OC) using intraperitoneal (IP) delivery of platinum (Pt)-based chemotherapy. The antitumor efficacy of IP chemotherapy is determined by efficient tumor tissue penetration. Although it is assumed that Pt penetration is limited to a few millimeters after IP delivery, little is known on the distribution of Pt in different tumor compartments at the ultrastructural level following IP administration. Here, using synchrotron radiation X-ray fluorescence spectrometry (SR-XRF) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), Pt distribution and penetration in OC peritoneal xenografts were determined at nanometer scale after IP chemoperfusion of cisplatin at 37-38°C or 40-41°C (hyperthermic). Using principal component analysis (PCA) the presence of phosphorus, manganese, calcium, zinc, iron, bromine, and sulfur was correlated with the distribution of Pt, while k-means analysis was used to quantify the amount of Pt in weight% in tumor stroma and in tumor cells. The results showed a heterogeneous distribution of Pt throughout the tumor, with an accumulation in the extracellular matrix. LA-ICP-MS mappings indicated significantly higher concentrations of Pt (P=0.0062) after hyperthermic chemoperfusion of cisplatin, while SR-XRF demonstrated a deeper tissue Pt penetration after hyperthermic treatment. Using PCA, it was showed that Pt co-localizes with bromine and sulfur. No differences were observed in Pt distribution regarding tumor cells and stroma, when comparing normo- vs. hyperthermic treatment. In conclusion, SR-XRF and LA-ICP-MS are suitable and highly sensitive techniques to analyze the penetration depth and distribution of Pt-based drugs after IP administration. To the best of our knowledge, this is the first experiment in which the distribution of Pt is analyzed at the cellular level after IP administration of cisplatin.


Assuntos
Neoplasias Ovarianas/ultraestrutura , Platina/farmacocinética , Animais , Cálcio/farmacocinética , Cisplatino/farmacocinética , Cobre/farmacocinética , Modelos Animais de Doenças , Feminino , Febre/metabolismo , Xenoenxertos/metabolismo , Xenoenxertos/ultraestrutura , Injeções Intraperitoneais , Espectrometria de Massas/métodos , Camundongos , Neoplasias Ovarianas/metabolismo , Fósforo/farmacocinética , Espectrometria por Raios X/métodos , Enxofre/farmacocinética , Distribuição Tecidual , Zinco/farmacocinética
8.
Bratisl Lek Listy ; 116(2): 119-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25665479

RESUMO

The objective of the present study was to investigate the effects of melatonin supplementation on elements in the liver of diabetic rats subjected to acute swimming exercise. Eighty adult male rats were equally divided into eight groups. Group 1, general control. Group 2, melatonin-supplemented control. Group 3, melatonin-supplemented diabetic control. Group 4, swimming control. Group 5, melatonin-supplemented swimming. Group 6, melatonin-supplemented diabetic swimming. Group 7, diabetic swimming. Group 8, diabetic control. Liver tissue samples were analyzed for lead, cobalt, molybdenum, chrome, sulphur, magnesium, manganese, sodium, potassium, phosphorus, copper, iron, calcium, zinc, selenium. The highest cobalt, chrome values were found in the groups 7, 8 and the groups 5, 6 respectively. Groups 3 and 7 had the highest copper values. Iron and potassium values were higher in the groups 1 and 4. Group 6 had increased magnesium value, and groups 6, 7, 8 were found to have the highest manganese levels. The highest lead values were found in the groups 5 and 6. Group 6 had the highest selenium levels. The highest zinc levels were established in 1 and 2. Groups 1, 2, 5 and 6 were found to have the highest calcium values. The results of our study indicate that melatonin supplementation in diabetes and forced exercise significantly alters the element metabolism in the liver (Tab. 3,Ref. 33).


Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/metabolismo , Fígado/metabolismo , Melatonina/farmacologia , Natação/fisiologia , Oligoelementos/farmacocinética , Animais , Cálcio/farmacocinética , Cromo/farmacocinética , Cobalto/farmacocinética , Cobre/farmacocinética , Diabetes Mellitus Experimental/sangue , Suplementos Nutricionais , Chumbo/farmacocinética , Magnésio/análise , Masculino , Condicionamento Físico Animal/métodos , Ratos , Ratos Sprague-Dawley , Selênio/farmacocinética , Enxofre/farmacocinética , Distribuição Tecidual , Zinco/farmacocinética
9.
Photosynth Res ; 119(3): 319-29, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24264737

RESUMO

The aim of this study was to characterize the roles of sulphur (S) nutrition in modulating the responses to iron (Fe) deficiency in the photosynthetic organelles of oilseed rape. Eight-week-old plants grown hydroponically were fed with S-sufficient or S-deprived solution with or without Fe(III)-EDTA. Responses to four S and Fe combined treatments were analysed after 5 and 10 days. Leaf chlorosis was generated by either S- or Fe-deprivation, with a decrease in chlorophyll and carotenoid content. These negative effects were more severe in the absence of S. The expression of Fe²âº transporter (IRT1) and Fe(III) chelate reductase (FRO1) gene was induced for the first 5 days and decreased after 10 days in the S-deprived roots, but largely improved by S supply even in the absence of Fe. Lack of ferric chelate reducing activity in the Fe-deprived roots in the absence of S was largely improved by S supply. The activity of photosynthesis, RuBisCO and sucrose synthase was closely related to S status in leaves. Electron microscopic observation showed that the Fe-deficiency in the absence of S greatly resulted in a severe disorganisation of thylakoid lamellae with loss of grana. However, these impacts of Fe-deficiency were largely restored in the presence of S. The present results indicate that S nutrition has significant role in ameliorating the damages in photosynthetic apparatus caused by Fe-deficiency.


Assuntos
Brassica napus/metabolismo , Ferro/metabolismo , Fotossíntese , Enxofre/metabolismo , Brassica napus/efeitos dos fármacos , Brassica napus/fisiologia , Carotenoides/metabolismo , Proteínas de Transporte de Cátions/genética , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , FMN Redutase/genética , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/metabolismo , Ferro/farmacologia , Organelas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/fisiologia , Estômatos de Plantas/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Enxofre/farmacocinética , Enxofre/farmacologia
10.
Planta ; 239(1): 79-96, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24068299

RESUMO

Sulfur (S) is an essential macronutrient for plants, and deficiency in soil S availability limits plant growth. Adaptive strategies have been evolved by plants to respond to S deficiency by coordinating systemic regulatory mechanism. A split-root experiment using legume model plant Medicago truncatula Gaertn. was conducted to investigate the systemic response to S deficiency. Plant growth, root morphology and S contents under varying conditions of S supply were determined, and the expression of genes encoding sulfate transporter (MtSULTRs) and MtAPR1 encoding an enzyme involved in S assimilation was monitored. Our results demonstrated that there was an apparent systemic response of M. truncatula to heterogeneous S supply in terms of root length, S contents, and S uptake and assimilation at the transcriptional level. When exposed to heterogeneous S supply, M. truncatula plants showed proliferation of lateral roots in S-rich medium and reduction in investment to S-depleted roots. Growth was stimulated with half-part of roots exposed to S-deficient medium. There were different expression patterns of MtSULTRs and MtAPR1 in response to heterogeneous S supply both in roots and shoots of M. truncatula. Expression of MtSULTR1.1 and MtSULTR1.3 was systemically responsive to S deficiency, leading to an enhancement of S uptake in roots exposed to S-sufficient medium. In addition, the response of S-deprived seedlings to re-supply of sulfate and Cys was also analyzed. It was shown that sulfate, but not Cys, may serve as a systemic signal to regulate the expression of genes associated with S absorption and assimilation in M. truncatula. These findings provide a comprehensive picture of systemic responses to S deficiency in leguminous species.


Assuntos
Medicago truncatula/metabolismo , Proteínas de Plantas/genética , Enxofre/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Meios de Cultura/química , Meios de Cultura/farmacologia , Cisteína/farmacologia , Regulação da Expressão Gênica de Plantas , Homeostase , Medicago truncatula/efeitos dos fármacos , Medicago truncatula/crescimento & desenvolvimento , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Solo , Sulfatos/farmacologia , Enxofre/farmacocinética
11.
ACS Appl Mater Interfaces ; 5(11): 5239-46, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23668422

RESUMO

In this study, we demonstrate a facile and environmentally friendly method for the synthesis of glutathione (GSH)-capped water-soluble CdS quantum dots (QDs) with a high cytocompatibility and a tunable optical property based on alkaline post-treatment of Cd-GSH coordination polymers (CPs). Cd-GSH CPs are synthesized with the coordination reaction of Cd(2+) with GSH at different pH values, and the CdS QDs are then formed by adding NaOH to the aqueous dispersion of the Cd-GSH CPs to break the coordination interaction between Cd(2+) and GSH with the release of sulfur. The particle size and optical property of the as-formed CdS QDs are found to be easily tailored by simply adjusting the starting pH values of GSH solutions used for the formation of Cd-GSH CPs, in which the wavelengths of trap-state emission of the QDs red-shift with an increase in the sizes of the QDs that is caused by an increase in the starting pH values of GSH solutions. In addition, the use of GSH as the capping reagent eventually endows the as-formed CdS QDs with enhanced water solubility and good cytocompatibility, as demonstrated with HeLa cells. The method demonstrated here is advantageous in that the cadmium precursor and the sulfur source are nontoxic and easily available, and the size, optical properties, water solubility, and cytocompatibilty of the as-formed CdS QDs are simply achieved and experimentally regulated. This study offers a new and green synthetic route to water-soluble and cytocompatible CdS QDs with tunable optical properties.


Assuntos
Materiais Biocompatíveis/química , Cádmio/química , Glutationa/química , Polímeros/química , Pontos Quânticos , Enxofre/química , Álcalis/química , Álcalis/farmacocinética , Materiais Biocompatíveis/farmacocinética , Cádmio/farmacocinética , Cor , Glutationa/farmacocinética , Células HeLa , Humanos , Luz , Microscopia Eletrônica de Transmissão , Polímeros/farmacocinética , Semicondutores , Solubilidade , Enxofre/farmacocinética , Água/química
12.
ScientificWorldJournal ; 2012: 657808, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629181

RESUMO

Mineral nutrients are the integral part of the agricultural systems. Among important plant nutrients, nitrogen (N) and sulphur (S) are known essential elements for growth, development, and various physiological functions in plants. Oleiferous brassicas (rapeseed and mustard) require higher amounts of S in addition to N for optimum growth and yield. Therefore, balancing S-N fertilization, optimization of nutrient replenishment, minimization of nutrient losses to the environment, and the concept of coordination in action between S and N could be a significant strategy for improvement of growth and productivity of oleiferous brassicas. Additionally, positive interaction between S and N has been reported to be beneficial for various aspects of oilseed brassicas. The current paper updates readers on the significance of N and S for the improvement of plant growth, development, and productivity in detail. In addition, S-N nutrition-mediated control of major plant antioxidant defense system components involved in the removal and/or metabolism of stress-induced/generated reactive oxygen species in plants (hence, the control of plant growth, development, and productivity) has been overviewed.


Assuntos
Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Nitrogênio/farmacocinética , Enxofre/farmacocinética , Agricultura/métodos
13.
Bioorg Med Chem Lett ; 18(3): 1241-4, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18191398

RESUMO

A series of selenophene analogues of the thiophene-containing antihypertensives milfasartan and eprosartan were prepared and tested for AT(1) receptor antagonist properties. All four selenophene compounds proved to be potent AT(1) receptor antagonists, with pK(B) estimates indicating that these selenides are at least as effective as the thiophene parent compounds at blocking AT(1) receptor mediated responses. These results reveal that replacement of sulfur with selenium in thiophene-containing sartans does not interfere with sartan activity.


Assuntos
Acrilatos/síntese química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/síntese química , Anti-Hipertensivos/síntese química , Imidazóis/síntese química , Compostos Organosselênicos/síntese química , Receptor Tipo 1 de Angiotensina/metabolismo , Tiofenos/síntese química , Acrilatos/química , Acrilatos/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Animais , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Cricetinae , Feminino , Imidazóis/química , Imidazóis/farmacologia , Estrutura Molecular , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacocinética , Ovário/citologia , Estereoisomerismo , Relação Estrutura-Atividade , Enxofre/química , Enxofre/farmacocinética , Tiofenos/química , Tiofenos/farmacocinética , Tiofenos/farmacologia
14.
Eur J Clin Nutr ; 62(9): 1106-15, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17538534

RESUMO

OBJECTIVE: Sulphites are widely used food additives that may damage health, hence limits are set on their use. They are excreted in urine as sulphate, along with sulphate derived from sulphur amino acids. Dietary intakes of sulphites are hard to determine, so we have tested the utility of urinary nitrogen:sulphate ratio as a biomarker of inorganic sulphur (IS) intake. Additionally we determined the half-life of ingested (34)SO(4)(2-) from its urinary excretion. SUBJECTS: Twenty healthy adult subjects were recruited by poster advertisement, for a 24-h study where they ate specified foods, which were high in IS, in addition to their normal diet. The half-life of ingested (34)SO(4)(2-) was assessed in five healthy volunteers, given 5.9 mmols of Na(2)(34)SO(4) as a single dose and collecting all urine specimens for 72-96 h. Urine and duplicate diets from three previously conducted studies were analysed for nitrogen and sulphate content, thus expanding the range of IS intakes for evaluation. METHODS: Duplicate diets were analysed for IS content by ion exchange chromatography, while IS intake was predicted from urinary sulphate (g/day S)-(urinary nitrogen (g/day)/18.89). (32)S:(34)S ratios were determined by liquid chromatography mass spectrometry/mass spectrometry. RESULTS: The range of IS intake was 1.3-37.5 mmol S/day. Actual and predicted IS intakes were mmol/day+/-s.e. 9.2+/-0.65 and 7.0+/-0.45, respectively, and were correlated r=0.60 (n=108). The mean half-life of ingested (34)SO(4)(2-) was 8.2 h. CONCLUSIONS: From a 24-h urine collection, IS intake from the habitual diet can be determined for groups of individuals. To predict individual intakes of IS, which may include high sporadic amounts from beer and wine, at least 48 h of urine collection would be required.


Assuntos
Enxofre/urina , Adulto , Biomarcadores/urina , Dieta , Proteínas Alimentares/urina , Feminino , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Nitrogênio/urina , Radioisótopos/farmacocinética , Radioisótopos/urina , Sulfatos/farmacocinética , Enxofre/administração & dosagem , Enxofre/farmacocinética , Adulto Jovem
15.
J Mater Sci Mater Med ; 19(7): 2581-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17665103

RESUMO

Near infrared (NIR) sensitive Au-Au(2)S nanoparticles are intensively being developed for biomedical applications including drug and gene delivery. Although all possible clinical applications will require compatibility of Au-Au(2)S nanoparticles with the biological milieu, their in vivo capabilities and limitations have not yet been explored. Au-Au(2)S nanoparticles and cisplatin-loaded Au-Au(2)S nanoparticles were successfully synthesized by the reduction of tetrachloroauric acid (HAuCl(4)) using sodium sulfide (Na(2)S), and cisplatin was loaded onto NIR sensitive Au-Au(2)S nanoparticles via an MUA (11-mercaptoundecanoic acid) layer. In this work, acute systemic toxicity in vivo, blood biochemistry assay, and tissue distribution in mice were carried out to further investigate the biocompatibility and biodistribution of these nanoparticles. The results from these studies demonstrated that both of nanoparticles (<200 microg/mL) might have a great advantage in biocompatibility and good biological safety.


Assuntos
Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Ouro/farmacocinética , Ouro/toxicidade , Nanopartículas/toxicidade , Enxofre/farmacocinética , Enxofre/toxicidade , Animais , Ouro/química , Dose Letal Mediana , Camundongos , Especificidade de Órgãos , Enxofre/química , Distribuição Tecidual
16.
J Zhejiang Univ Sci B ; 8(10): 731-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17910116

RESUMO

Field experiments were conducted at Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan, during winter 2003-2004 and 2004-2005 to evaluate the effect of nitrogen and sulfur levels and methods of nitrogen application on canola (Brassica napus L. cv. Bulbul-98) under rainfed conditions. Four levels of S (0, 10, 20, and 30 kg/ha) and three levels of N (40, 60, and 80 kg/ha) and a control treatment with both nutrients at zero level were included in the experiments. Sulfur levels were applied at sowing while N levels were applied by three methods (100% soil application, 90% soil+10% foliar application, and 80% soil +20% foliar application). The experiments were laid out in randomized complete block (RCB) design having four replications. Oil content increased significantly up to 20 kg S/ha but further increase in S level did not enhance oil content. Glucosinolate content increased from 13.6 to 24.6 micromol/g as S rate was increased from 0 to 30 kg/ha. Protein content increased from 22.4% to 23.2% as S rate was increased from 0 to 20 kg/ha. Oil content responded negatively to the increasing N levels. The highest N level resulted in the highest values for protein (23.5%) and glucosinolate (19.9 micromol/g) contents. Methods of N application had no significant impact on any parameters under study.


Assuntos
Brassica napus/efeitos dos fármacos , Brassica napus/fisiologia , Fertilizantes , Nitrogênio/administração & dosagem , Nitrogênio/farmacocinética , Enxofre/administração & dosagem , Enxofre/farmacocinética , Brassica napus/classificação
17.
Food Addit Contam ; 24 Suppl 1: 26-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17687697

RESUMO

Progress in developing genetic and agronomic approaches for reducing the levels of the principal precursors of acrylamide, asparagine and sugars in crop plants is reviewed. The factors that affect asparagine and sugar accumulation, particularly in cereal seeds and potato tubers, are described. Asparagine levels appear to be the key parameter in determining acrylamide formation in processed wheat flour and agronomic strategies for reducing asparagine accumulation in wheat grain are reviewed. Sulphur availability has been shown to be particularly important, with sulphur deprivation causing a dramatic increase in grain asparagine levels and acrylamide risk. Nitrogen availability is also a factor, with increasing nitrogen availability causing grain asparagine levels and acrylamide risk to rise. In potato, attention has been focused on sugars, and there has been some success in reducing sugar accumulation in stored potatoes by genetic modification, with a resultant reduction in acrylamide formation. However, the wisdom or otherwise of this dogma is discussed. Other possible genetic targets for manipulation or development as genetic markers in breeding programmes are reviewed. Plant breeders and farmers are encouraged to exploit the varietal differences in acrylamide risk that have already been identified and to develop good agronomic practice to reduce the levels of acrylamide precursors in cereals and potato.


Assuntos
Acrilamida/metabolismo , Carcinógenos Ambientais/metabolismo , Produtos Agrícolas/química , Contaminação de Alimentos/análise , Acrilamida/análise , Agricultura/métodos , Asparagina/análise , Asparagina/genética , Disponibilidade Biológica , Metabolismo dos Carboidratos/genética , Carcinógenos Ambientais/análise , Produtos Agrícolas/genética , Exposição Ambiental/efeitos adversos , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/métodos , Nitrogênio/farmacocinética , Enxofre/farmacocinética
18.
J Dairy Sci ; 90(6): 3034-43, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17517746

RESUMO

Six commercial dairies from south central Idaho were surveyed to estimate the whole-farm surpluses of magnesium (Mg), sulfur (S), copper (Cu), and zinc (Zn). Mineral imports and exports were monitored in a 12-mo period and samples from the diets, feeds, feces, urine, and manure were collected at regular farm visits. Soils from manure-amended fields were sampled in the spring and fall. In all cases, the largest import of Mg, S, Cu, and Zn to the dairy was with purchased feeds, from 91 (S) to 97% (Zn) of all imports. The major mineral export item was manure [from 60% (S) to 89% (Cu) of all exports] and forages, in the case of a dairy with a large land base. Export with milk represented on average only 8.6, 25, 2.1, and 11% (Mg, S, Cu, and Zn, respectively) of all exports. Thus, the conversion of the imported feed Mg, S, Cu, and Zn into milk was rather low (on a whole-farm scale): 5.6, 11, 1.4, and 5.2%, respectively. Concentrations of Mg, Cu, and Zn in the lactating cow diets from the participating dairies exceeded National Research Council (2001) recommendations on average by 85, 34, and 73%, respectively, which contributed to the inefficient use of imported minerals. Whole-farm Mg surplus varied from 4 to 54 t/yr (3 to 19 kg/cow per year). The efficiency of use of imported Mg varied from 27 to 88%. Sulfur surpluses were from 9 to 52 t/yr (12 to 40 kg/cow per year). Copper and Zn surpluses were also significant (average of 59 and 585 kg/yr and 0.05 and 0.4 kg/cow per year, respectively). The average efficiency of use of imported S, Cu, and Mg was 44, 62, and 56%, respectively and, as with Mg, varied significantly among the dairies. The results from this study suggest that reduction in the concentration of dietary Mg, Cu, and Zn is potentially the most efficient way of reducing overall excretions and whole-farm surpluses of these minerals.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Indústria de Laticínios/métodos , Esterco/análise , Leite/química , Agricultura , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cobre/farmacocinética , Monitoramento Ambiental/métodos , Poluição Ambiental/prevenção & controle , Feminino , Idaho , Lactação/metabolismo , Magnésio/farmacocinética , Necessidades Nutricionais , Solo/análise , Enxofre/farmacocinética , Zinco/farmacocinética
19.
Biol Trace Elem Res ; 106(3): 231-45, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16141471

RESUMO

To elucidate compositional changes of the cardiac valves in monkey with aging, the authors investigated age-related changes of elements in the four cardiac valves of rhesus and Japanese monkeys and the relationships among elements by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The four cardiac valves of the aortic, pulmonary, mitral, and tricuspid valves were resected from 19 rhesus and 11 Japanese monkeys, ranging in age from 10 d to 33 yr. The element contents were determined by ICP-AES. It was found that the Ca, P, S, and Zn contents were high in the four cardiac valves of the monkeys below 1 yr and thereafter decreased significantly with aging, except for Ca in the mitral valve, for which no significant correlation was found between age and Ca content. The Ca and P contents did not increase in the four cardiac valves at old age. This result revealed that calcification scarcely occurred in the four cardiac valves at old age. With regard to the relationships among elements, it was found that there were significant direct correlations among the Ca, P, S, and Zn contents in all of the four cardiac valves of the monkeys, with two exceptions between P and Zn contents in both the aortic and pulmonary valves. Therefore, as Ca decreased in the four cardiac valves, P, S, and Zn decreased simultaneously in the same cardiac valves.


Assuntos
Cálcio/farmacocinética , Valvas Cardíacas/química , Fósforo/farmacocinética , Enxofre/farmacocinética , Zinco/farmacocinética , Envelhecimento/fisiologia , Animais , Macaca/fisiologia , Macaca mulatta/fisiologia , Espectrofotometria Atômica
20.
Biotechnol Prog ; 21(3): 781-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15932256

RESUMO

A new type of air-lift reactor with immobilized Gordonia nitida CYKS1 cells on a fibrous support was designed and used for the biocatalytic desulfurization (BDS) of diesel oil. Its performance was evaluated at different phase ratios of the oil to the aqueous medium (or oil phase fractions) and different sucrose concentrations. When the reaction mixture contained 10% diesel oil (v/v), 61-67% of sulfur was removed as the sulfur content decreased from 202-250 to 76-90 mg L(-1) in 72 h. The sulfur content did not decrease any further because the remaining sulfur compounds were recalcitrant to BDS. During the desulfurization, the strain CYKS1 consumed hydrocarbons in the diesel oil, mainly n-alkanes with 10-26 carbons, as carbon source even though an easily available carbon source, sucrose, was supplied.


Assuntos
Reatores Biológicos/microbiologia , Técnicas de Cultura de Células/instrumentação , Gasolina , Bactéria Gordonia/metabolismo , Hidrocarbonetos/farmacocinética , Enxofre/farmacocinética , Ar , Catálise , Desenho de Equipamento , Análise de Falha de Equipamento , Bactéria Gordonia/classificação , Projetos Piloto , Especificidade da Espécie , Enxofre/química
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