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1.
Plant Sci ; 330: 111636, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36791961

RESUMO

Camelina (Camelina sativa) is an emerging industrial oilseed crop because of its potential for double cropping, fallow year production, growth on marginal lands, and multiple uses of seed oils and meals. To realize the potential for sustainable production of camelina, a better understanding of how camelina seed oil production and composition respond to low input environments is desired. Phosphorus (P) is one of the least available essential macronutrients to plants with finite worldwide supply. This study investigated seed oil production and lipid composition of camelina in field settings and under greenhouse conditions in response to P deficiency. Lipidomic profiling reveals that P deficiency in field settings triggered extensive leaf lipid remodeling that decreased the ratio of phospholipids to non-P-containing galactolipids from 30% to 5% under P sufficient to deficient conditions. P deficiency increased seed oil content per seed weight by approximately 25% and 20% in field and greenhouse settings, respectively. In addition, P deficiency altered seed fatty acid composition, with increases in monounsaturated 18:1 and 20:1 and decreases in polyunsaturated 18:3. Total seed production was decreased by 10- to 15-fold under P deficiency and the decrease resulted from reduced seed numbers without affecting seed weight. The results from field and greenhouse conditions indicate that P deficiency increases seed oil content, alters fatty acid composition, and decreases greatly seed production, suggesting that achieving a high yield and quality of camelina seed oil is positively linked to P status of soil.


Assuntos
Brassicaceae , Óleos de Plantas , Sementes , Ácidos Graxos , Fosfatos
2.
Sci Total Environ ; 859(Pt 1): 159964, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36372177

RESUMO

China is promoting the production and use of electric vehicles (EVs) to achieve carbon neutrality. However, the shift will drive higher demand and tighter supply of nickel in China. We develop a stock-driven bottom-up dynamic substance flow analysis (SFA) model to simulate the demand trends of various EVs under 3 scenarios, the flow of nickel under 9 scenarios and the amount of recoverable nickel under 27 scenarios in China's EV industry from 2010 to 2050. The results indicate that China's current production capacity and primary reserves of nickel cannot meet the growing nickel demand, especially under the High EVs-LNCT scenarios, and closed-loop nickel recovery from EV batteries can effectively alleviate the demand-supply contradiction. In different scenarios, the annual recycling nickel could cover between 67.7 % and 96.6 % of the demand for EV batteries in 2050, and between 37.9 % and 58.1 % in terms of the cumulative quantity by 2050. When the low nickel battery technology is adopted and the recovery efficiency is rapidly improved, the recovered nickel would meet the demand for EV batteries to the highest degree. Therefore, sufficient attention should be paid to low-nickel battery technology and efficient recycling of spent EV batteries, which is of great significance to ensure the development of EV industry and the availability of nickel in China.


Assuntos
Fontes de Energia Elétrica , Níquel , Reciclagem , Eletricidade , Indústrias , China
3.
ACS Appl Mater Interfaces ; 13(48): 56909-56922, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34807583

RESUMO

Stroke is the second leading cause of death globally and the most common cause of severe disability. Several barriers need to be addressed more effectively to treat stroke, including efficient delivery of therapeutic agents, rapid release at the infarct site, precise imaging of the infarct site, and drug distribution monitoring. The present study aimed to develop a bio-responsive theranostic nanoplatform with signal-amplifying capability to deliver rapamycin (RAPA) to ischemic brain tissues and visually monitor drug distribution. A pH-sensitive theranostic RAPA-loaded nanoparticle system was designed since ischemic tissues have a low-pH microenvironment compared with normal tissues. The nanoparticles demonstrated good stability and biocompatibility and could efficiently load rapamycin, followed by its rapid release in acidic environments, thereby improving therapeutic accuracy. The nano-drug-delivery system also exhibited acid-enhanced magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) imaging signal properties, enabling accurate multimodal imaging with minimal background noise, thus improving drug tracing and diagnostic accuracy. Finally, in vivo experiments confirmed that the nanoparticles preferentially aggregated in the ischemic hemisphere and exerted a neuroprotective effect in rats with transient middle cerebral artery occlusion (tMCAO). These pH-sensitive multifunctional theranostic nanoparticles could serve as a potential nanoplatform for drug tracing as well as the treatment and even diagnosis of acute ischemic stroke. Moreover, they could be a universal solution to achieve accurate in vivo imaging and treatment of other diseases.


Assuntos
Materiais Biomiméticos/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Nanopartículas/química , Fármacos Neuroprotetores/uso terapêutico , Sirolimo/uso terapêutico , Nanomedicina Teranóstica , Doença Aguda , Animais , Materiais Biomiméticos/química , Concentração de Íons de Hidrogênio , AVC Isquêmico/diagnóstico por imagem , Teste de Materiais , Fármacos Neuroprotetores/química , Células PC12 , Tamanho da Partícula , Ratos , Sirolimo/química
4.
Biotechnol Biofuels ; 14(1): 49, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33640013

RESUMO

BACKGROUND: Lipid transporters play an essential role in lipid delivery and distribution, but their influence on seed oil production in oilseed crops is not well studied. RESULTS: Here, we examined the effect of two lipid transporters, FAX1 (fatty acid export1) and ABCA9 (ATP-binding cassette transporter subfamily A9) on oil production and lipid metabolism in the oilseed plant Camelina sativa. Overexpression (OE) of FAX1 and ABCA9 increased seed weight and size, with FAX1-OEs and ABCA9-OEs increasing seed length and width, respectively, whereas FAX1/ABCA9-OEs increasing both. FAX1-OE and ABCA9-OE displayed additive effects on seed oil content and seed yield. Also, OE of FAX1 and ABCA9 affected membrane lipid composition in developing pods, especially on phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol. The expression of some genes involved in seed oil synthesis, such as DGAT2, PDAT1, and LEC1, was increased in developing seeds of FAX1- and/or ABCA9-OEs. CONCLUSION: These results indicate that increased expression of FAX1 and ABCA9 can potentially be applied to improving camelina oil production.

5.
New Phytol ; 226(4): 1055-1073, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32176333

RESUMO

Plant oils are valuable commodities for food, feed, renewable industrial feedstocks and biofuels. To increase vegetable oil production, here we show that the nonspecific phospholipase C6 (NPC6) promotes seed oil production in the Brassicaceae seed oil species Arabidopsis, Camelina and oilseed rape. Overexpression of NPC6 increased seed oil content, seed weight and oil yield both in Arabidopsis and Camelina, whereas knockout of NPC6 decreased seed oil content and seed size. NPC6 is associated with the chloroplasts and microsomal membranes, and hydrolyzes phosphatidylcholine and galactolipids to produce diacylglycerol. Knockout and overexpression of NPC6 decreased and increased, respectively, the flux of fatty acids from phospholipids and galactolipids into triacylglycerol production. Candidate-gene association study in oilseed rape indicates that only BnNPC6.C01 of the four homeologues NPC6s is associated with seed oil content and yield. Haplotypic analysis indicates that the BnNPC6.C01 favorable haplotype can increase both seed oil content and seed yield. These results indicate that NPC6 promotes membrane glycerolipid turnover to accumulate TAG production in oil seeds and that NPC6 has a great application potential for oil yield improvement.


Assuntos
Brassicaceae , Brassicaceae/genética , Ácidos Graxos , Fosfolipases , Óleos de Plantas , Plantas Geneticamente Modificadas , Sementes
6.
BMC Plant Biol ; 17(1): 222, 2017 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-29178835

RESUMO

BACKGROUND: Subtribe Orchidinae (Orchidaceae, Orchidoideae) are a nearly cosmopolitan taxon of terrestrial orchids, comprising about 1800 species in 47 to 60 genera. Although much progress has been made in recent years of phylogenetics of Orchidinae, considerable problems remain to be addressed. Based on molecular phylogenetics, we attempt to illustrate the phylogenetic relationships and discuss generic delimitation within Orchidinae. Seven DNA markers (five plastid and two nuclear), a broad sampling of Orchidinae (400 species in 52 genera) and three methods of phylogenetic analysis (maximum likelihood, maximum parsimony and Bayesian inference) were used. RESULTS: Orchidinae s.l. are monophyletic. Satyrium is sister to the rest of Orchidinae s.l. Brachycorythis and Schizochilus are successive sister to Asian-European Orchidinae s.s. Sirindhornia and Shizhenia are successive sister to clade formed by Tsaiorchis-Hemipilia-Ponerorchis alliance. Stenoglottis is sister to the Habenaria-Herminium-Peristylus alliance. Habenaria, currently the largest genus in Orchidinae, is polyphyletic and split into two distant clades: one Asian-Australian and the other African-American-Asian. Diplomeris is sister to Herminium s.l. plus Asian-Australian Habenaria. CONCLUSIONS: We propose to recognize five genera in the Ponerorchis alliance: Hemipilia, Ponerorchis s.l., Sirindhornia, Shizhenia and Tsaiorchis. Splitting Habenaria into two genera based on morphological characters and geographical distribution may be the least disruptive approach, and it is reasonable to keep Satyrium in Orchidinae.


Assuntos
Orchidaceae/classificação , DNA de Plantas , Marcadores Genéticos , Orchidaceae/genética , Filogenia
7.
Orthop Surg ; 9(3): 296-303, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28960817

RESUMO

OBJECTIVE: To study the corrosion behavior of magnesium alloy surface treated with micro-arc oxidation and hydrothermal deposition in living animals. METHODS: A magnesium oxide (MgO) layer was prepared on Mg alloy using micro-arc oxidation technology, and then a composite coating composed of magnesium hydroxide, hydroxyapatite, and MgO was coated on the MgO layer using the hydrothermal deposition method for 2 h and 24 h. Male 3-month-old white New Zealand rabbits (n = 48) weighting 2200-2300 g, were divided into four groups randomly. The prepared Mg alloy samples with composite coatings were implanted into the femoral medullary cavity of rabbits. For the Mg group, bare Mg samples without any treatment were implanted; for the MgO group, bare Mg samples undergoing MAO treatment were implanted; for the HT2h group, samples of the MgO group undergoing hydrothermal treatment (HT) for 2 h were implanted; and for the HT24h group, samples of group MgO undergoing HT for 24 h were implanted. Then the in vivo corrosion behaviors of implants were evaluated by X-ray observation, micro-CT analysis and serum Mg2+ examination. RESULTS: The X-ray showed that samples implanted in animals were decreased as time went by. The micro-CT showed that on the fourth week, the residual volume percentages (RVP) of samples of the Mg, MgO, HT2h, and HT24h groups were 72.81% ± 2.10%, 71.68% ± 1.49%, 81.14% ± 1.54%, and 82.04% ± 0.89%, respectively; on the eighth week, the RVP of four groups were 29.45% ± 1.06%, 41.82% ± 1.13%, 53.92% ± 0.37%, and 62.53% ± 2.06%, respectively; while on the 12th week, RVP were 8.45% ± 0.49%, 9.97% ± 0.75%, 37.09% ± 0.89%, 46.71% ± 1.87%. The RVP of the HT2h group and the HT24h group were higher than for the Mg group and the MgO group for all three time points (P < 0.05); the RVP for HT24h was higher than for HT2h at 8 and 12 weeks, and the differences were significant, indicating that the degradation of Mg alloy slowed down after composite coating. In addition, the composite-coated Mg alloy by 24-h hydrothermal treatment exhibited a slower degradation than that treated by 2 h. Serum Mg2+ concentration results showed that on the second week, the Mg2+ concentrations of the Mg, MgO, HT2h, and HT24h groups were 2.24 ± 0.10 mmol/L, 2.12 ± 0.07 mmol/L, 2.06 ± 0.11 mmol/L, and 2.15 ± 0.12 mmol/L, respectively. On the fourth week, these concentrations were 1.99 ± 0.33 mmol/L, 2.18 ± 0.06 mmol/L, 2.17 ± 0.09 mmol/L, and 2.13 ± 0.14 mmol/L, respectively. On the eighth week, the concentrations were 2.22 ± 0.09 mmol/L, 2.20 ± 0.17 mmol/L, 2.06 ± 0.11 mmol/L, and 2.14 ± 0.07 mmol/L, respectively. On the 12th week, the concentrations were 2.18 ± 0.04 mmol/L, 2.20 ± 0.08 mmol/L, 2.09 ± 0.02 mmol/L, and 2.16 ± 0.11 mmol/L. CONCLUSION: The combination of micro-arc oxidation and hydrothermal deposition can greatly improve the anti-corrosion behavior of Mg alloy, and Mg alloy coated with this composite coating is a promising biomaterial with a satisfactory degradation rate.


Assuntos
Materiais Revestidos Biocompatíveis/química , Magnésio/química , Próteses e Implantes , Ligas/química , Animais , Corrosão , Durapatita/química , Hidróxido de Magnésio/química , Óxido de Magnésio/química , Masculino , Oxirredução , Coelhos , Propriedades de Superfície , Microtomografia por Raio-X
8.
Analyst ; 140(19): 6595-601, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26300105

RESUMO

Being high throughput, rapid, automated, economical, convenient to operate and highly sensitive, protein arrays have been widely used in the analysis of tumor markers and veterinary drug residues. Pathogenic microbes also can be detected qualitatively by DNA array or protein array; however, their high throughput detection and quantification remains a big obstacle. To evaluate the potentiality of protein arrays for multiple quantitative detection of microorganisms with naked eye examination without the help of any equipment, here we developed a visual-antibody-macroarray (VAMA) aiming at rapid and simultaneous quantification of Escherichia coli O157:H7 and Shigella boydii. The results show that this VAMA is highly specific and is able to distinguish mixed Escherichia coli O157:H7 and Shigella boydii synchronously. The detection limits are equivalent to 3.4 × 10(5) CFU mL(-1) and 3.2 × 10(5) CFU mL(-1), respectively, which conform to the results of plate counting and ELISA. Importantly, the examination can be solely performed with the naked eye. Therefore, we provide an easy, reliable and rapid method for quantitative analysis of microorganisms.


Assuntos
Anticorpos Monoclonais/imunologia , Escherichia coli O157/isolamento & purificação , Análise Serial de Proteínas/métodos , Shigella boydii/isolamento & purificação , Colódio/química , Escherichia coli O157/imunologia , Limite de Detecção , Membranas Artificiais , Shigella boydii/imunologia , Fatores de Tempo
9.
Mol Phylogenet Evol ; 69(3): 950-60, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23811435

RESUMO

Dendrobium is one of the three largest genera and presents some of the most intricate taxonomic problems in the family Orchidaceae. Based on five DNA markers and a broad sampling of Dendrobium and its relatives from mainland Asia (109 species), our results indicate that mainland Asia Dendrobium is divided into eight clades (with two unplaced species) that form polytomies along the spine of the cladogram. Both Dendrobium and Epigeneium are well supported as monophyletic, whereas sect. Dendrobium, sect. Densiflora, sect. Breviflores, sect. Holochrysa, are paraphyletic/polyphyletic. Many ignored phylogenetic relationships, such as the one of major clades formed by D. jenkinsii and D. lindleyi (two members of sect. Densiflora), the Aphyllum group, the Devonianum group, the Catenatum group, the Crepidatum group, and the Dendrobium moniliforme complex are well supported by both molecular and morphological evidence. Based on our data, we propose to broaden sect. Dendrobium to include sect. Stuposa, sect. Breviflores, and sect. Holochrysa and to establish a new section to accommodate D. jenkinsii and D. lindleyi. Our results indicated that it is preferable to use a broad generic concept of Dendrobium and to pursue an improved infrageneric classification at sectional level, taking into account both morphology and current molecular findings.


Assuntos
Dendrobium/classificação , Filogenia , Ásia , Teorema de Bayes , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Dendrobium/anatomia & histologia , Dendrobium/genética , Marcadores Genéticos , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA
10.
Blood ; 114(2): 338-45, 2009 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-19417207

RESUMO

IMiDs immunomodulatory drugs, including lenalidomide and pomalidomide represent a novel class of small molecule anticancer and anti-inflammatory drugs with broad biologic activities. However, the molecular mechanism through which these drugs exert their effects is largely undefined. Using pomalidomide and primary human monocytes, we report that pomalidomide rapidly and selectively activated RhoA and Rac1, but not Cdc42 or Ras, in the absence of any costimulation. Consistent with the activation of Rho GTPases, we found that pomalidomide enhanced F-actin formation, stabilized microtubules, and increased cell migration, all of which were blocked by selective inhibitors of ROCK1 and Rac1. Further, we showed that in Swiss 3T3 cells, pomalidomide only activated RhoA, not Rac1 or Cdc42, and potently induced stress fiber formation. The pomalidomide effect on actin cytoskeleton was blocked by the ROCK1 inhibitor, but not Rac1 inhibitor. Finally, we demonstrated that pomalidomide was able to regulate the activity of Rho GTPases and the formation of F-actin in primary human T cells as it did in monocytes and showed that the activation of RhoA was essential for pomalidomide-induced interleukin-2 expression in T cells. These novel activities provide what we believe a critical mechanism by which IMiDs drugs function as therapeutic immunomodulatory agents.


Assuntos
Citoesqueleto/efeitos dos fármacos , Citoesqueleto/enzimologia , Imunossupressores/farmacologia , Talidomida/análogos & derivados , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Citoesqueleto/imunologia , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-2/genética , Interleucina-2/imunologia , Interleucina-2/metabolismo , Camundongos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/enzimologia , Linfócitos T/imunologia , Talidomida/farmacologia
11.
Cell Signal ; 18(7): 982-93, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16199137

RESUMO

IKK-i and TBK1 were recently identified as IKK-related kinases that are activated by toll-like receptors TLR3 and TLR4. These kinases were identified as essential components of the virus-activated as well as LPS-MyD88 independent kinase complex that phosphorylates IRF3 and results in the production of cytokines involved in innate immunity. Both IKK-i and TBK1 have also been implicated in the activation of the NFkappaB pathway but the precise mechanism is not clear. Although the literature to date suggests that IKK-i and TBK1 play redundant roles in TLR3 and TLR4 signaling, recent data suggest that there may be subtle differences in the signaling pathways affected by these kinases. We have generated tetracycline-inducible stable cell lines that express a wild type or kinase-inactive mutant form of IKK-i. Our data suggest that expression of IKK-i can activate both NFkappaB and IRF3, leading to the production of several cytokines including interferon beta. IKK-i most likely acts upstream of IKK2 to activate NFkappaB in these cells since expression of the kinase-inactive version of IKK-i did not inhibit TNFalpha mediated production of inflammatory cytokines. The data suggest that IKK-i is not involved in TNF-alpha mediated signaling but instead could likely play a role in activating IKK2 downstream of Toll-like receptor signaling. We also identified STAT1, Tyk2, and JAK1 as secondary mediators of IKK-i signaling as a result of interferon beta production in these cells.


Assuntos
Citocinas/biossíntese , Fator Regulador 3 de Interferon/fisiologia , NF-kappa B/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Linhagem Celular , Quimiocina CCL5/biossíntese , Quimiocina CXCL10 , Quimiocinas CXC/biossíntese , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Humanos , Quinase I-kappa B , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/biossíntese , Interleucina-8/biossíntese , Janus Quinase 1 , Mutação , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , TYK2 Quinase , Tetraciclina/farmacologia , Fator de Necrose Tumoral alfa/fisiologia
12.
J Cell Biochem ; 86(4): 613-23, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12210728

RESUMO

Fanconi anemia (FA), a genetic disorder predisposing to aplastic anemia and cancer, is characterized by hypersensitivity to DNA-damaging agents and oxidative stress. Five of the cloned FA proteins (FANCA, FANCC, FANCE, FANCF, FANCG) appear to be involved in a common functional pathway that is required for the monoubiquitination of a sixth gene product, FANCD2. Here, we report that FANCA associates with the IkappaB kinase (IKK) signalsome via interaction with IKK2. Components of the FANCA complex undergo rapid, stimulus-dependent changes in phosphorylation, which are blocked by kinase-inactive IKK2 (IKK2 K > M). When exposed to mitomycin C, cells expressing IKK2 K > M develop a cell cycle abnormality characteristic of FA. Thus, FANCA may function to recruit IKK2, thus providing the cell a means of rapidly responding to stress.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Proteínas Nucleares , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/metabolismo , Adenoviridae/genética , Animais , Sítios de Ligação , Linhagem Celular Transformada , Clonagem Molecular , Proteína do Grupo de Complementação C da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Fase G2/fisiologia , Vetores Genéticos , Células HeLa/enzimologia , Humanos , Quinase I-kappa B , Proteínas I-kappa B/metabolismo , Cinética , Mitomicina/farmacologia , Inibidor de NF-kappaB alfa , Fosforilação , Testes de Precipitina , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Proteínas/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais/fisiologia , Transfecção , Fator de Necrose Tumoral alfa/farmacologia , Técnicas do Sistema de Duplo-Híbrido
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