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1.
R Soc Open Sci ; 6(9): 191069, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31598323

RESUMO

Perfluorooctane sulfonate (PFOS) was listed as a persistent organic pollutant by the Stockholm Convention. As a typical alternative to PFOS, sodium p-perfluorous nonenoxybenzene sulfonate (OBS) has recently been detected in the aquatic environment which has caused great concern. For the first time, the adsorption behaviour and mechanism of OBS on activated carbon (AC) with different physical and chemical properties were investigated. Decreasing the particle size of AC can accelerate its adsorption for OBS, while AC with too small particle size was not conducive to its adsorption capacity due to the destruction of its pore structure during the mechanical crushing process. Intra-particle diffusion had a lesser effect on the adsorption rate of AC with smaller particle size, higher hydrophilicity and larger pore size. Reactivation of AC by KOH can greatly enlarge their pore size and surface area, greatly increasing their adsorption capacities. The adsorption capacity of two kinds of R-GAC exceeded 0.35 mmol g-1, significantly higher than that of other ACs. However, increasing the hydrophilicity of AC would decrease their adsorption capacities. Further investigation indicated that a larger pore size and smaller particle size can greatly enhance the adsorptive removal of OBS on AC in systems with other coexisting PFASs and organic matter due to the reduction of the pore-blocking effect. The spent AC can be successfully regenerated by methanol, and it can be partly regenerated by hot water and NaOH solution. The percentage of regeneration for the spent AC was 70.4% with 90°C water temperature and up to 95% when 5% NaOH was added into the regeneration solution. These findings are very important for developing efficient adsorbents for the removal of these newly emerging PFASs from wastewater and understanding their interfacial behaviour.

2.
J Colloid Interface Sci ; 557: 655-663, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561082

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are widely used and co-exist in various aquatic environments, but their co-removal is not clear. In this study, the competitive adsorption behavior and mechanism of six traditional and emerging PFASs on anion-exchange resin IRA67 in the bisolute and mixed systems were studied. The adsorption equilibrium of the long-chain PFASs was at least 96 h whereas 48 h was required for the short-chain PFASs. When the PFASs were co-removed in the bisolute system, their competition was not obvious at low PFAS concentration of 0.01597 mmol/L due to the relatively adequate adsorption sites. When the concentrations of PFASs were increased to 0.07666 mmol/L, the removal of perfluorobutanoic acid (PFBA) and perfluorobutane sulfonate (PFBS) decreased by 77.78% and 72.09%, respectively. The competitive experiments showed that the adsorbed short-chain PFASs could be replaced by the long-chain ones, which was closely related to their hydrophobicity, backbone and functional groups. With the increase of solution pH from 3 to 7, the polyamine groups on the resin IRA67 were transferred to the base forms and the effective adsorption sites decreased, resulting in a more obvious competitive replacement behavior. This study suggested that the PFASs with long chain could be more effectively removed from the coexisting PFASs solution by the anion-exchange resins, and the short-chain PFASs in water may be removed when high dosage of anion-exchange resins is applied or the solution pH is decreased.

3.
Hum Reprod ; 34(8): 1587-1594, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31305926

RESUMO

STUDY QUESTION: Does maternal periconceptional no folic acid supplementation have an increased risk of neural tube defects (NTDs) associated with previous spontaneous abortion or first-trimester fever? SUMMARY ANSWER: Maternal periconceptional no folic acid supplementation can increase the risk of NTDs associated with previous spontaneous abortion or first-trimester fever, independent of known confounding factors. WHAT IS KNOWN ALREADY: Maternal periconceptional folic acid deficiency can increase the risk of NTDs. However, whether an interaction between periconceptional no folic acid supplementation and history of spontaneous abortion or first-trimester fever may have an increased risk of NTDs remains unknown. STUDY DESIGN, SIZE, DURATION: A population-based case-control study was performed including 104 nuclear families with offspring with NTDs and 100 control families with normal offspring between 1993 and 2002. PARTICIPANTS/MATERIALS, SETTING, METHODS: We investigated the potential interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion or first-trimester fever in the risk for NTDs. Information on exposure factors was obtained at the onset of pregnancy, and pregnancy outcomes were collected during the first week after delivery or at the time of termination of the pregnancy. A multivariate logistic regression analysis was performed. MAIN RESULTS AND THE ROLE OF CHANCE: The interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion markedly increased the risk of NTDs (adjusted odds ratio (aOR) 18.68, 95% CI, 4.43-78.76) after adjusting for potential confounding factors. The interaction coefficient was found to be 2.08, higher than 1, indicating that there is a significant interaction between two factors. Mothers who did not take periconceptional folic acid and had first-trimester fever had an increased risk of NTDs (aOR 21.81, 95% CI, 8.81-80.73). However, the interaction coefficient was found to be 0.62, less than 1, indicating that there is no significant interaction between two factors. LIMITATIONS, REASONS FOR CAUTION: A potential limitation was that the interval between the previous spontaneous abortion and the beginning of the subsequent pregnancy could not be estimated accurately, but was at least 1 year or more. WIDER IMPLICATIONS OF THE FINDINGS: We emphasize that a previous spontaneous abortion may represent a first occurrence of NTDs rather than be the cause of NTDs. Our findings indicate that mothers with a history of spontaneous abortion are ideal candidates for periconceptional folic acid supplementation. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by National Natural Science Foundation of China (41871360) and Danone Nutrition Center for Dietary Nutrition Research and Education Foundation (DIC2015-05). There are no competing interests to declare.

4.
Cell Biochem Funct ; 37(2): 72-83, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30773657

RESUMO

Cancer cell progression and proliferation increase cell density, resulting in changes to the tumour site, including the microenvironment. What is not known is if increased cell density influences the aggressiveness of cancer cells, especially their proliferation, migration, and invasion capabilities. In this study, we found that dense cell culture enhances the aggressiveness of the metastatic cancer cell lines, 4T1 and ZR-75-30, by increasing their proliferation, migration, and invasion capabilities. However, a less metastatic cell line, MCF-7, did not show an increase in aggressiveness, following dense cell culture conditions. We conducted a differential proteomic analysis on 4T1 cells cultured under dense or sparse conditions and identified an increase in expression for proteins involved in migration, including focal adhesion, cytoskeletal reorganization, and transendothelial migration. In contrast, 4T1 cells grown under sparse conditions had higher expression levels for proteins involved in metabolism, including lipid and phospholipid binding, lipid and cholesterol transporter activity, and protein binding. These results suggest that the high-density tumour microenvironment can cause a change in cellular behaviour, leading towards more aggressive cancers. SIGNIFICANCE OF THE STUDY: Metastasis of cancer cells is an obstacle to the clinical treatment of cancer. We found that dense cultures made metastatic cancer cells more potent in terms of proliferation, migration, and invasion. The proteomic and bioinformatic analyses provided some valuable clues for further intensive studies about the effects of cell density on cancer cell aggressiveness, which were associated with events such as pre-mRNA splicing and RNA transport, focal adhesion and cytoskeleton reorganization, ribosome biogenesis, and transendothelial migration, or associated with proteins, such as JAM-1 and S100A11. This investigation gives us new perspectives to investigate the metastasis mechanisms related to the microenvironment of tumour sites.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias Mamárias Animais/metabolismo , Proteínas de Neoplasias/metabolismo , Proteômica , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/genética
5.
Sci Rep ; 7(1): 10509, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28874726

RESUMO

We investigated cytosolic calcium (Ca2+) and sarcoplasmic reticulum Ca2+ regulation in skeletal muscle fibers of hibernating Daurian ground squirrels (Spermophilus dauricus), non-hibernating hindlimb-unloaded (HLU) squirrels, and HLU rats to clarify the molecular mechanisms involved in preventing muscle atrophy in hibernators. The Na+, K+-ATPase and Ca2+-ATPase activities in the soleus muscle (SOL) of squirrels were maintained in hibernation, decreased during interbout arousal (IB-A), and increased to autumn/pre-hibernation (AUT/Pre-H) levels in torpor after interbout arousal (Post-IBA), whereas activities in the extensor digitorum longus muscle (EDL) were stable during hibernation, but increased during post-hibernation (Post-H). Activities increased in the SOL of HLU rats, but were stable in HLU squirrels. Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) activity in the SOL decreased in IB-A squirrels, but returned to AUT/Pre-H levels in the Post-IBA group; no significant changes were found in the EDL. SERCA activity increased in the EDL of HLU squirrels and SOL of HLU rats. Compared with AUT/Pre-H, SERCA type 2 protein expression increased in the SOL and EDL of IB-A and Post-IBA squirrels, but increased in the SOL only in HLU animals. We also describe the protein kinase A changes in this paper. Thus, hibernating ground squirrels displayed remarkable Na+, K+-ATPase, Ca2+-ATPase, and SERCA plasticity.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Atrofia Muscular/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Sciuridae/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Expressão Gênica , Hibernação , Atrofia Muscular/etiologia , Ratos
6.
Neuroscience ; 336: 81-101, 2016 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-27586053

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by beta-amyloid (Aß) deposition, neurofibrillary tangles and cognitive decline. Recent pharmacologic studies have found that ATP-sensitive potassium (KATP) channels may play a role in AD and could be a potential therapeutic target. Interestingly, these channels are found in both neurons and astrocytes. One of the hallmarks associated with AD is reactive gliosis and a change in astrocytic function has been identified in several neuropathological conditions including AD. Thus the goal of this study was to examine whether the pore-forming subunits of KATP channels, Kir6.1 and Kir6.2, are altered in the hippocampus in a cell type-specific manner of the 3xTg-AD mouse model of AD and in human AD tissue obtained from the Chinese brain bank. Specifically, in old 3xTg-AD mice, and age-matched controls, we examined glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), Kir6.1 and Kir6.2 in hippocampal region CA1 with a combination of immunoblotting and immunohistochemistry (IHC). A time point was selected when memory impairment and histopathological changes have been reported to occur in 3xTg-AD mice. In human AD and age-matched control tissue IHC experiments were performed using GFAP and Kir6.2. In the hippocampus of 3xTg-AD mice, compared to wild-type controls, Western blots showed a significant increase in GFAP indicating astrogliosis. Further, there was an increase in Kir6.2, but not Kir6.1 in the plasma membrane fraction. IHC examination of hippocampal region CA1 in 3xTg-AD sections revealed an increase in Kir6.2 immunoreactivity (IR) in astrocytes as identified by GFAP and GS. In human AD tissue similar data were obtained. There was an increase in GFAP-IR in the stratum oriens (SO) and alveus (ALV) of CA1 concomitant with an increase in Kir6.2-IR in cells with an astrocytic-like morphology. Dual immunofluorescence revealed a dramatic increase in co-localization of Kir6.2-IR and GFAP-IR. Taken together, these data demonstrate that increased Kir6.2 is seen in reactive astrocytes in old 3xTg-AD mice and human AD tissue. These changes could dramatically alter astrocytic function and subsequently contribute to AD phenotype in either a compensatory or pathophysiological manner.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Hipocampo/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Animais , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/patologia , Humanos , Masculino , Camundongos , Neurônios/metabolismo , Proteínas tau/metabolismo
7.
J Exp Bot ; 67(11): 3481-96, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27117341

RESUMO

AtDjB1 is a mitochondria-located J-protein in Arabidopsis thaliana It is involved in the regulation of plant growth and development; however, the exact mechanisms remain to be determined. We performed comparison analyses of phenotypes, auxin signalling, redox status, mitochondrial structure and function using wild-type plants, AtDjB1 mutants, rescued AtDjB1 mutants by AtDjB1 or YUCCA2 (an auxin synthesis gene), and AtDjB1 overexpression plants. AtDjB1 mutants (atj1-1 or atj1-4) exhibited inhibition of growth and development and reductions in the level of IAA and the expression of YUCCA genes compared to wild-type plants. The introduction of AtDjB1 or YUCCA2 into atj1-1 largely rescued phenotypic defects and the IAA level, indicating that AtDjB1 probably regulates growth and development via auxin. Furthermore, atj1-1 plants displayed a significant reduction in amount/activity of mitochondrial complex I compared to wild-type plants; this resulted in the accumulation of reactive oxygen species (ROS). Moreover, exogenous H2O2 markedly inhibited the expression of YUCCA genes in wild-type plants. In contrast, the reducing agent ascorbate increased the expression of YUCCA genes and IAA level in atj1-1 plants, indicating that the low auxin level observed in atj1-1 was probably due to the high oxidation status. Overall, the data presented here suggest that AtDjB1 is required for mitochondrial complex I activity and regulates growth and development through ROS-mediated auxin signalling in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Complexo I de Transporte de Elétrons/metabolismo , Proteínas de Choque Térmico HSP40/genética , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Transdução de Sinais , Arabidopsis/enzimologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Oxigenases de Função Mista , NADH Desidrogenase , Espécies Reativas de Oxigênio/metabolismo
8.
Front Neuroanat ; 9: 109, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26321922

RESUMO

Cells expressing doublecortin (DCX+) occur at cortical layer II, predominantly over the paleocortex in mice/rats, but also across the neocortex among larger mammals. Here, we explored the time of origin of these cells in neonatal and 2-month-old guinea pigs following prenatal BrdU pulse-chasing. In the neocortex, BrdU+ cells birth-dated at embryonic day 21 (E21), E28, and E35 laminated over the cortical plate with an inside-out order. In the piriform cortex, cells generated at E21 and E28 occurred with a greater density in layer II than III. Many cells were generated at later time points until birth, occurring in the cortex without a laminar preference. DCX+ cells in the neocortex and piriform cortex partially co-colocalized with BrdU (up to 7.5%) in the newborns after pulse-chasing from E21 to E49 and in the 2 month-old animals after pulse-chasing from E28 to E60/61, with higher rates seen among the E21-E35 groups. Together, layer II DCX+ cells in neonatal and young adult guinea pigs may be produced over a wide prenatal time window, but mainly during the early phases of corticogenesis. Our data also show an earlier establishment of the basic lamination in the piriform relative to neocortical areas in guinea pigs.

9.
Patient Prefer Adherence ; 8: 1449-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25364235

RESUMO

BACKGROUND: Although surveys conducted in Western countries have shown that the levonorgestrel-releasing intrauterine system (LNG-IUS; Mirena(®)) is well accepted by European women, its acceptance by Chinese women is not yet clearly known. The purpose of this study was to analyze the experiences and levels of satisfaction with Mirena among Chinese women living in 12 different cities. METHODS: In total, 1,021 women who attended 21 medical centers for insertion of Mirena were invited to complete a questionnaire regarding their contraceptive decision at baseline (preinsertion), and two further questionnaires on their experience and satisfaction with Mirena at 3-6 months and 1 year after insertion. RESULTS: At baseline, 36% of women self-reported heavy or very heavy menstrual bleeding, while 41% reported normal bleeding. The majority of women (98%) were satisfied with the preinsertion counseling, during which contraceptive reliability was identified as the most important reason for considering Mirena. Continuation rates for Mirena were 99% at 3-6 months and 93% at 12 months after insertion, and most women (92% and 93%, respectively) had less bleeding at these times. The percentage of women who rated Mirena as better than their previous contraceptive method was 63%. Overall, around 90% of respondents were very satisfied or rather satisfied with Mirena, and 64% stated that they would recommend it to their friends. CONCLUSION: These data suggest that continuation and satisfaction rates with Mirena were very high, and that the device is well accepted by Chinese women.

10.
New Phytol ; 194(2): 364-78, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22356282

RESUMO

AtDjB1 belongs to the J-protein family in Arabidopsis thaliana. Its biological functions in plants are largely unknown. In this study, we examined the roles of AtDjB1 in resisting heat and oxidative stresses in A. thaliana using reverse genetic analysis. AtDjB1 knockout plants (atj1-1) were more sensitive to heat stress than wildtype plants, and displayed decreased concentrations of ascorbate (ASC), and increased concentrations of hydrogen peroxide (H(2)O(2)) and oxidative products after heat shock. Application of H(2)O(2) accelerated cell death and decreased seedling viability in atj1-1. Exogenous ASC conferred much greater thermotolerance in atj1-1 than in wildtype plants, suggesting that a lower concentration of ASC in atj1-1 could be responsible for the increased concentration of H(2)O(2) and decreased thermotolerance. Furthermore, AtDjB1 was found to localize to mitochondria, directly interact with a mitochondrial heat-shock protein 70 (mtHSC70-1), and stimulate ATPase activity of mtHSC70-1. AtDjB1 knockout led to the accumulation of cellular ATP and decreased seedling respiration, indicating that AtDjB1 modulated the ASC concentration probably through affecting the function of mitochondria. Taken together, these results suggest that AtDjB1 plays a crucial role in maintaining redox homeostasis, and facilitates thermotolerance by protecting cells against heat-induced oxidative damage.


Assuntos
Adaptação Fisiológica , Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/fisiologia , Citoproteção , Proteínas de Choque Térmico HSP40/metabolismo , Temperatura Alta , Estresse Oxidativo , Adaptação Fisiológica/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Ácido Ascórbico/farmacologia , Respiração Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Técnicas de Inativação de Genes , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Proteínas Mitocondriais/metabolismo , Mutação/genética , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Plântula/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo
11.
Yao Xue Xue Bao ; 43(3): 295-8, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18630267

RESUMO

To synthesize aristolochic acid (AA)-2'-deoxyguanosine 5'-monophosphate (dGp) adducts in vitro and develop a novel method for the characterization of the adducts using multiple mass spectrometric techniques. AA was incubated with dGp in vitro using either enzymatic activation (by xanthine oxidase) or chemical activation (by zinc) to synthesize AA-dGp adducts, and the reaction conditions were optimized. Crude extracts were analyzed by techniques of liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-MS/MS) and high accuracy mass data and isotope pattern of super high resolution Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICRMS). The quasi-molecular ion peaks of the AA-dGp adducts were obtained in the negative ion mode. Analysis by electrospray ionization/tandem mass spectrometry (ESI-MS/MS) provided useful structural information about AA-dGp adducts. AA can bind covalently to the exocyclic amino group of deoxyguanosine to form AA-dGp adducts. MS analysis is a powerful tool to detect and identify AA-dGp adducts simply, rapidly and accurately.


Assuntos
Ácidos Aristolóquicos/síntese química , Adutos de DNA/síntese química , DNA/química , Desoxiguanosina/química , Ácidos Aristolóquicos/química , Cromatografia Líquida de Alta Pressão/métodos , DNA/metabolismo , Espectrometria de Massas em Tandem/métodos
12.
Phys Rev Lett ; 88(11): 113902, 2002 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-11909402

RESUMO

We report on an ultrafast longitudinal time measurement by a nonresonant Rayleigh-type nondegenerate four-wave mixing (NFWM). We investigated the field-correlation effects on Rayleigh-type NFWM by examining the time-delayed dependence of the NFWM spectra. Based on the field-correlation effects, a time-delayed method is proposed to suppress the thermal effect, and ultrafast relaxation time can be measured even in an absorbing medium.

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