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1.
Mar Pollut Bull ; 150: 110712, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31718860

RESUMO

Global climate change has attracted worldwide attention. The ocean is the largest active carbon pool on the planet and plays an important role in global climate change. However, marine plastic pollution is getting increasingly serious due to the large consumption and mismanagement of global plastics. The impact of marine plastics on ecosystem responsible for the gas exchange and circulation of marine CO2 may cause more greenhouse gas emissions. Consequently, in this paper, threats of marine microplastics to ocean carbon sequestration are discussed. Marine microplastics can 1) affect phytoplankton photosynthesis and growth; 2) have toxic effects on zooplankton and affect their development and reproduction; 3) affect marine biological pump; and 4) affect ocean carbon stock. Phytoplankton and zooplankton are the most important producer and consumer of the ocean. As such, clearly, further research should be needed to explore the potential scale and scope of this impact, and its underlying mechanisms.

2.
Acta Diabetol ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31820107

RESUMO

AIMS: Recent studies have suggested a possible association between microbiota and gestational diabetes (GDM). However, the results are inconsistent. Our objective was to investigate further the relationship between GDM and microbiota and verify the potential microbial marker. METHODS: Two complementary approaches were used for the demonstration. First, we compared the gut microbial composition of 23 GDM patients and 26 non-GDM ethnically Chinese Han pregnant women, by using whole-metagenome shotgun sequencing of their stool samples collected at the third trimester. Second, we used Q-PCR (quantitative polymerase chain reaction) to evaluate the gut microbial composition in the stool samples from another cohort of 150 Chinese pregnant women (113 Control and 37 GDM), to further confirm the potential microbial marker. RESULTS: The gut microbiota of GDM women show lower albeit not statistically significant (p = 0.18) alpha diversity at the species level than non-GDM women. However, the species-level beta-diversity or between-sample diversity measured by Bray-Curtis distance shows significant differences (p < 2.2e-16) between the two groups. The species Bacteroides dorei positively correlated with both OGTT (oral glucose tolerance test) 0-Hour (p = 0.0099) and OGTT 1-Hour (p = 0.0070). There is a similar trend between Bacteroides sp. 3_1_33FAA and both OGTT 0-Hour (p = 0.014) and OGTT 1-Hour (p = 0.0101) response variables. The species Alistipes putredinis negatively correlated with OGTT 1-Hour (p = 0.0172) and OGTT 2-Hour (p = 0.0147). Q-PCR validation further confirmed the association between the glucose tolerance loci of Bacteroides dorei and OGTT response. CONCLUSIONS: Gut microbiome is related to the diabetic status of Chinese women during pregnancy. Specific species such as Bacteroides dorei associate with glucose response and could be potential monitoring and therapeutic microbial markers for GDM.

3.
Chemosphere ; 244: 125486, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31812050

RESUMO

There is a lack of research on microplastic pollution in freshwater areas. In this study, microplastic pollution in lakeshore sediments of East Dongting Lake was investigated. The abundance of microplastics ranged from 180 to 693 items/kg in the lakeshore sediment, which was moderate compared with other areas of the world. Fibers, transparent and small sized microplastics accounted for the largest proportion in terms of shape, color and size, respectively. Eight types of microplastics with different polymer compositions were identified by micro-Raman spectroscopy. The study found that the abundance of microplastics in the urban area sediment of Dongting Lake is lower than that of the rural area. The difference in environmental protection measures between urban and rural areas may be the cause of this phenomenon. The results of this study is helpful for understanding the role of human activities in microplastic pollution and provide valuable references for future research.

4.
Bioinformatics ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31626280

RESUMO

MOTIVATION: Microbiome analyses of clinical samples with low microbial biomass are challenging because of the very small quantities of microbial DNA relative to the human host, ubiquitous contaminating DNA in sequencing experiments, and the large and rapidly growing microbial reference databases. RESULTS: We present CSMD, a bioinformatics pipeline specifically developed to generate accurate species-level microbiome profiles for clinical samples with low microbial loads. CSMD applies strategies for the maximal elimination of host sequences with minimal loss of microbial signal and effectively detects microorganisms present in the sample with minimal false positives using a stepwise convergent solution. CSMD was benchmarked in a comparative evaluation with other classic tools on previously published well-characterized datasets. It showed higher sensitivity and specificity in host sequence removal and higher specificity in microbial identification, which led to more accurate abundance estimation. All these features are integrated into a free and easy-to-use tool. Additionally, CSMD applied to cell-free plasma DNA showed that microbial diversity within these samples is substantially broader than previously believed. AVAILABILITY: CSMD is freely available at https://github.com/liuyu8721/csmd. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

5.
J Clin Transl Hepatol ; 7(3): 213-220, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31608212

RESUMO

Background and Aims: Ravidasvir (RDV) is a new generation pangenotypic hepatitis C virus (HCV) NS5A inhibitor, with high barrier to baseline resistance-associated species. This is the first phase 2/3 study conducted in Mainland China confirming the efficacy and safety of RDV + ritonavir-boosted danoprevir + ribavirin for 12 weeks in treatment-naïve noncirrhotic patients with genotype 1 infection in a large population. Methods: In this multicenter, randomized, double-blinded, placebo-controlled phase 2/3 trial (NCT03362814), we enrolled 424 treatment-naïve, noncirrhotic adult HCV genotype 1 patients. All patients were randomized at 3:1 ratio to receive a combination of RDV 200mg once daily plus ritonavir-boosted danoprevir 100mg/100mg twice daily and oral ribavirin 1000/1200mg/day (body weight <75/≥75 kg) (n = 318) or placebo (n = 106) for 12 weeks. The primary end-point was the rate of sustained virologic response 12 weeks after the end of treatment, and the safety was evaluated and compared between treatment and placebo groups. Results: The overall rate of sustained virological response at 12 weeks after treatment is 99% (306/309, 95%, CI: 97%-100%) under per protocol set analysis. All patients harboring baseline NS5A resistance-associated species in the treatment group (76/76, per protocol set) achieved sustained virological response at 12 weeks after treatment. No treatment-related serious adverse events were reported. Laboratory abnormalities showed mild or moderate severity (grade 1 and grade 2) in liver function tests. Conclusions: In treatment-naïve, noncirrhotic HCV Chinese patients infected with HCV genotype 1, all-oral regimen of RDV + ritonavir-boosted danoprevir + ribavirin for 12 weeks was highly efficacious, safe, and well tolerated.

6.
J Clin Transl Hepatol ; 7(3): 221-225, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31608213

RESUMO

Background and Aims: Genotype (GT) 1 remains the predominant hepatitis c virus (HCV) GT in Chinese patients. Over 80% of those Chinese patients harbor the interferon-sensitive CC allele of IFNL4rs12979860, which is favorable for interferon-based treatment regimens. This phase III clinical trial aimed to evaluate the efficacy and safety of the ritonavir-boosted danoprevir plus pegylated-interferon α-2a and ribavirin regimen for 12 weeks in treatment-naïve mainland Chinese patients infected with HCV GT1 without cirrhosis. Methods: One hundred and forty-one treatment-naïve, non-cirrhotic HCV GT1 Chinese patients (age ≥18 years) were enrolled for this single-arm, multicenter, phase III MANASA study (NCT03020082). Patients received a combination of ritonavir-boosted danoprevir (100 mg/100 mg) twice a day plus subcutaneous injection of weekly pegylated-interferon α-2a (180 µg) and oral ribavirin (1000/1200 mg/day body weight <75/≥75 kg) for 12 weeks. The primary end-point was sustained virologic response rate at 12 weeks after the end of treatment. The secondary end-points were safety outcomes, tolerability, virologic response over time and relapse rate. Results: All enrolled patients were HCV GT1-infected, and most among them (97.9%, 123/141) had the HCV GT1b subtype. Single-nucleotide polymorphism test showed that the majority of patients were of the IFNL4 rs12979860 CC genotype (87.2%, 123/141). Overall, 140 patients completed the 12-week treatment, and 97.1% (136/140) patients achieved sustained virologic response at 12 weeks (per protocol population group, 95% confidence interval: 92.9-99.2%). Only drug-related serious adverse event occurred. Most of the adverse events were grade 1 and grade 2 alanine aminotransferase elevation or liver dysfunction. One patient discontinued treatment because of severe head injury in a car accident. Conclusions: The triple regimen of ritonavir-boosted danoprevir plus pegylated-interferon α-2a and ribavirin produced a sustained virologic response rate of 97.1% after 12 weeks treatment in noncirrhotic HCV GT1-infected Chinese patients, and was safe and well tolerated. Trial Registration Clinical-Trials.gov Identifier: NCT03020082.

7.
Bioresour Technol ; 293: 122102, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31514120

RESUMO

This work evaluated the possibility of lead (Pb2+), cadmium (Cd2+) and copper (Cu2+) ions synergic scavenging by a chloro-phosphate impregnated biochar (CPBC) from aqueous solution. Adsorption experiments displayed that the adsorption capacity of heavy metals by CPBC can be improved better compared with the pristine biochar (BC). The X-ray diffraction (XRD) analysis further demonstrated that the precipitation of Pb5(PO4)3Cl, Cd5(PO4)3Cl and Cu3(PO4)3 might be responsible for Pb2+, Cd2+ and Cu2+ scavenging. The competitive adsorption exhibited that Pb2+, Cd2+ and Cu2+ would compete for the same adsorption sites of CPBC when they coexisted and the adsorption affinity of CPBC was observed in the following order: Pb2+ > Cd2+ > Cu2+. The available phosphorus results suggested that the combination of biochar with phosphate materials can both improve the adsorption performance and reduce the risk of eutrophication by using phosphate materials which can provide a promising application for multiple heavy metals scavenging.


Assuntos
Cádmio , Cobre , Adsorção , Carvão Vegetal , Chumbo , Fosfatos
8.
Front Immunol ; 10: 1950, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31475011

RESUMO

CD4+ T cell mediated uveitis is conventionally treated with systemic immunosuppressive agents, including corticosteroids and biologics targeting key inflammatory cytokines. However, their long-term utility is limited due to various side effects. Here, we investigated whether DNA methylation inhibitor zebularine can target CD4+ T cells and control intraocular inflammation. Our results showed that zebularine restrained the expression of inflammatory cytokines IFN-γ and IL-17 in both human and murine CD4+ T cells in vitro. Importantly, it also significantly alleviated intraocular inflammation and retinal tissue damage in the murine experimental autoimmune uveitis (EAU) model in vivo, suggesting that the DNA methylation inhibitor zebularine is a candidate new therapeutic agent for uveitis.

9.
Sci Total Environ ; 697: 134200, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31491631

RESUMO

With the convenience of plastic products to daily life, the negative sides of the plastic-age have gradually emerged. Like other pollutants, complex environmental factors result in the ubiquitous presence of (micro)plastics worldwide, raising potential risks to the ecological systems. However, due to the limitation of traditional technologies in treating these materials, new strategies should be developed. More recently, researchers have showed that biotechnology strategies could be promising approaches to effectively manage and control (micro)plastics in the environment, because some microorganisms have been confirmed to be successfully capable of degrading (micro)plastics. Nevertheless, the biotechnology is still in its infancy, and most studies are carried out under laboratory conditions. The biodegradation process is affected by many factors: microorganism species, carbon sources, material types and sizes. Problematically, (micro)plastics are highly stable in the environment, which are difficult to be used as carbon sources for microorganisms. Biodegradation of (micro)plastics requires appropriate conditions, which are not always feasible in field conditions. As such, although biotechnology strategies might be a promising approach to remove environmental (micro)plastics, we believe it is not now at least.


Assuntos
Biodegradação Ambiental , Biotecnologia , /análise , Ecossistema , Monitoramento Ambiental
10.
Curr Mol Med ; 19(6): 434-442, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31288713

RESUMO

BACKGROUND: Age-related macular degeneration (AMD) is a progressive and irreversible eye disease. The anti-vascular endothelial growth factor (VEGF) therapy has revolutionized the treatment of neovascular AMD. However, the expense for such treatment is quite high. METHODS: We used a traditional Chinese medicine ZQMT as an alternative therapeutic regimen for AMD. We employed two in vivo animal models mimicking dry and wet AMD respectively to assess the therapeutic efficacy of ZQMT on treating AMD-related retinopathy. AMD-related retinopathy in Crb1rd8 mice was evaluated from week 1 to 8 by fundus photography. Laser-induced choroidal neovascularization (CNV) was evaluated by fluorescein angiography and histopathology. RESULTS: ZQMT increased CX3CR1 expression in murine CD4+ T cells either cultured in vitro or directly isolated from animals treated with ZQMT. We also performed both in vitro and in vivo studies to confirm that ZQMT has no apparent toxic effects. ZQMT alleviated AMD-related retinopathy in both Crb1rd8 and CNV models. Depletion of CCL2 and CX3CR1 in Crb1rd8 mice abolished the efficacy of ZQMT, suggesting that CCL2 and/or CX3CR1 may underlie the mechanisms of ZQMT in treating AMD-related retinopathy in mice. CONCLUSION: In summary, our study supports the protective roles of a traditional Chinese medicine ZQMT in AMD.

11.
Environ Pollut ; 252(Pt A): 511-521, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31167159

RESUMO

Nanoplastics have attracted increasing attention in recent years due to their widespread existence in the environment and the potential adverse effects on living organisms. In this paper, the toxic effects of nanoplastics on organisms were systematically reviewed. The translocation and absorption of nanoplastics, as well as the release of additives and contaminants adsorbed on nanoplastics in the organism body were discussed, and the potential adverse effects of nanoplastics on human health were evaluated. Nanoplastics can be ingested by organisms, be accumulated in their body and be transferred along the food chains. Nanoplastics showed effects on the growth, development and reproduction of organisms, and disturbing the normal metabolism. The toxic effects on living organisms mainly depended on the surface chemical properties and the particle size of nanoplastics. Positively charged nanoplastics showed more significant effects on the normal physiological activity of cells than negatively charged nanoplastics, and smaller particle sized nanoplastics could more easily penetrate the cell membranes, hence, accumulated in tissues and cells. Additionally, the release of additives and contaminants adsorbed on nanoplastics in organism body poses more significant threats to organisms than nanoplastics themselves. However, there are still knowledge gaps in the determination and quantification of nanoplastics, as well as their contaminant release mechanisms, degradation rates and process from large plastics to nanoplastics, and the transportation of nanoplastics along food chains. These challenges would hinder the risk assessment of nanoplastics in the environment. It is necessary to further develop the risk assessment of nanoplastics and deeply investigate its toxicological effects.


Assuntos
Bivalves/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Nanopartículas/toxicidade , Nematoides/efeitos dos fármacos , Plásticos/toxicidade , Animais , Cadeia Alimentar , Humanos , Nanopartículas/análise , Tamanho da Partícula , Plásticos/análise , Propriedades de Superfície
12.
Artigo em Inglês | MEDLINE | ID: mdl-31083601

RESUMO

As emerging pollutants, microplastics have attracted the attention of scholars from all over the world. However, there is a lack of research on freshwater areas, even in densely populated urban areas. This study investigated eight urban lakes in Changsha, China. It was found that microplastic concentrations ranged from 2425 ± 247.5 items/m3 to 7050 ± 1060.66 items/m3 in the surface water of research areas and the maximum concentration was found in Yuejin Lake, a tourist spot in the center of the city. Anthropogenic factors are an important reason for microplastic abundance in urban lakes. The major shape of microplastics was linear and most of the microplastics were transparent. More than 89.5% of the microplastics had a size of less than 2 mm. Polypropylene was the dominant type in the studied waters. This study can provide a valuable reference for a better understanding of microplastic pollution in urban areas of China.


Assuntos
Monitoramento Ambiental , Lagos/análise , Plásticos/análise , Poluentes Químicos da Água/análise , China , Cidades , Poluição Química da Água/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-30888403

RESUMO

PURPOSE: To investigate the change of IL-10 producing regulatory B cells (Bregs), which function to suppress peripheral immune responses, in patients with thyroid associated ophthalmopathy (TAO). METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy controls (N=54), patients with Grave's disease (N=26), and TAO patients (N=125), and stimulated with CpG/CD40L. The frequency of IL-10 producing Bregs and the expression of IL-10 in response to thyroid-stimulating hormone (TSH) stimulation were measured by flow cytometry. CD4+ T cells were cultured with Breg-depleted PBMCs to elucidate the function of Bregs in TAO patients. The potential immunoregulatory mechanism was also investigated by western blot and chromatin immunoprecipitation assays. RESULTS: Active TAO patients had higher baseline levels of Bregs in their peripheral blood than both healthy controls and inactive patients. TSH promoted Bregs. Bregs from TAO patients were defective in suppressing the activation of IFN-γ+ and IL-17+ T cells in vitro. CONCLUSIONS: We found that regulatory B cells in TAO patients are functionally defective, suggesting the defective Bregs might be responsible for the pathogenesis of TAO.

14.
Bioresour Technol ; 283: 277-285, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30921580

RESUMO

Innovative carbonaceous nano-chlorapatites (CNClAPs) which originated from the pyrolyzation of the mixture of bamboo residues and chlorapatites varying from 400 °C to 600 °C were used to investigate the decontamination efficacy of lead (Pb2+) and tetracycline (TC) from wastewater. Rising pyrolytic temperature can highly improve the decontamination efficacy, of which CNClAP600 exhibited the most remarkable effects for Pb2+ and TC decontamination (90.37% for Pb2+ and 86.58% for TC at pH = 7). The kinetic, isotherm and characterization analysis demonstrated that the inner mechanisms for the decontamination of Pb2+ and TC involved precipitation, electrostatic interaction, hydrogen bonding, π-π interaction and pore filling. Experiment indicated that the enhancement and competitive adsorption resulted from the interaction between Pb2+ and TC could facilitate their joint decontamination under low concentrations. This research shed light on the management of coexisting heavy metals and organic matters contamination in wastewater by CNClAPs under different temperatures.


Assuntos
Antibacterianos/isolamento & purificação , Chumbo/isolamento & purificação , Nanocompostos , Tetraciclina/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Descontaminação , Concentração de Íons de Hidrogênio , Cinética
15.
Environ Pollut ; 249: 91-98, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30884397

RESUMO

The Tibet Plateau, the so-called Third Pole of the world, is home to the headstreams of many great rivers. The levels of microplastic pollution in those rivers, however, are unknown. In this study, surface water and sediment samples were collected from six sampling sites along five different rivers. The surface water and sediment samples were collected with a large flow sampler and a stainless steel shovel, respectively. The abundance of microplastics ranged from 483 to 967 items/m3 in the surface water and from 50 to 195 items/kg in the sediment. A large amount of small, fibrous, transparent microplastics were found in this study. Five types of microplastics with different chemical compositions were identified using micro-Raman spectroscopy: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyamide (PA). These results demonstrate that rivers in the Tibet Plateau have been contaminated by microplastics, not only in developed areas with intense human activity but also in remote areas, where microplastic pollution requires further attention.


Assuntos
Monitoramento Ambiental , Plásticos/análise , Poluentes Químicos da Água/análise , Poluição Ambiental , Polietileno/análise , Polipropilenos/análise , Poliestirenos , Rios/química , Análise Espectral Raman , Tibet , Água
16.
Chemosphere ; 222: 865-871, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30753965

RESUMO

Bentonite is a natural and environmentally clay mineral, and bentonite-derived mesoporous materials (BDMMs) were obtained conveniently from the alkali and acid treatment of bentonite. In the present study, BDMMs were explored for immobilization of laccase obtained from Trametes versicolor. As a result, bentonite-derived mesoporous materials-Laccase (BDMMs-Lac) was developed for the removal of tetracycline (TC). The enzyme immobilization process was carried out through physical adsorption contact (ion exchange adsorption, hydrogen bond adsorption, and Van der waals adsorption) between the BDMMs and laccase. The process of immobilization remarkably increased its operating temperature. The BDMMs-Lac exhibited over 60% removal efficiency for TC within 3 h in the presence of 1-hydroxybenzotriazole (HBT). In conclusion, BDMMs-Lac showed more promising potential than free laccase for practical continuous applications.


Assuntos
Bentonita/química , Enzimas Imobilizadas/química , Lacase/química , Tetraciclina/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Minerais , Temperatura Ambiente , Trametes/enzimologia
17.
Mar Pollut Bull ; 139: 328-331, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30686434

RESUMO

Micro(nano)plastics, as emerging contaminants, have attracted worldwide attention. Nowadays, the environmental distribution, sources, and analysis methods and technologies of micro(nano)plastics have been well studied and recognized. Nevertheless, the role of micro(nano)plastic particles as vectors for attaching organisms is not fully understood. In this paper, the role of micro(nano)plastics as vectors, and their potential effects on the ecology are introduced. Micro(nano)plastics could 1) accelerate the diffusion of organisms in the environment, which may result in biological invasion; 2) increase the gene exchange between attached biofilm communities, causing the transfer of pathogenic and antibiotic resistance genes; 3) enhance the rate of energy, material and information flow in the environment. Accordingly, the role of microplastics as vectors for organisms should be further evaluated in the future research.


Assuntos
Biofilmes , Ecotoxicologia/métodos , Nanoestruturas , Plásticos , Microbiologia da Água , Animais , Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental/métodos , Espécies Introduzidas , Plâncton , Poluentes Químicos da Água
18.
Chemosphere ; 217: 843-850, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30458419

RESUMO

Malachite green effluent with the Coexistence of Cd (П) was efficiently decolorized by kaolinite-laccase (Kaolin-Lac). Laccase from Trametes versicolor was immobilized onto the kaolinite through physical adsorption contact. The optimal conditions were 180 min of immobilization time and 0.8 mg/mL of enzyme solution. Kaolin-Lac could obtain a loading efficiency of 88.22%, a loading capacity of 12.25 mg/g, and the highest activity of 839.01 U/g. Moreover, the process of immobilization increased its pH stability and operational stability. Kaolin-Lac retained above 50% of the original activity and nearly 80% decolorization for MG after 5 cycles. In the presence of 3, 5-Dimethoxy-4-hydroxybenzaldehyde (SA), Kaolin-Lac could degrade over 98% of malachite green. The coexistence of Cd (П) was beneficial to the decolorization of malachite green by Kaolin-Lac. The structural and morphological features of kaolinite, Kaolin-Lac and Kaolin-Lac after degradation were determined by scanning electron microscopy-energy spectrum analysis (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR). Cadmium appeared on the Kaolin-Lac after degradation. After immobilization and degradation, the surface groups on kaolinite were changed. Kaolin-Lac showed its more potential continuous employment than free laccase in practical malachite green dyes effluent mixed with Cd (П).


Assuntos
Cádmio/química , Enzimas Imobilizadas/química , Caulim/química , Lacase/química , Corantes de Rosanilina/química , Adsorção , Cor , Corantes , Lacase/metabolismo , Trametes/enzimologia
19.
J Colloid Interface Sci ; 534: 357-369, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30243177

RESUMO

A green synthesized gold-catalyst (PDA-g-C3N4/Au) for highly efficient reduction of nitroaromatics by NaBH4 was proposed. Polydopamine (PDA) served as the reductant and stabilizer for AuNPs reduction, avoiding the use of chemical reductant and stabilizer that may result in secondary contamination. g-C3N4 not only acted as the support but also provided compatibility for AuNPs deposition, enhancing the stability and deposition of AuNPs, which improved the catalytic activity. Different experimental parameters including the amount of Au loading, concentration of NaBH4, and dosage of catalyst were studied. Results showed that PDA-g-C3N4/Au(3) revealed higher catalytic activity with a rate constant of 0.0514 s-1 and TOF of 545.60 h-1 for 4-NP reduction. In addition, the catalyst was highly efficient in reduction of other nitroaromatics and the reduction rates of these compounds were found as the sequence: methyl orange > 2-nitrophenol > 2, 4-dinitrophenol > Erichrome Black T > Congo red. Moreover, the PDA-g-C3N4/Au(3) catalyst kept high stability and excellent conversion efficiency over ten reduction cycles. The practical application on different real water samples suggests that this Au catalyst has promising application in environmental water purification. The simple and green synthetic Au catalyst expands the range of application and provides potential application on environmental remediation.

20.
Syst Biol Reprod Med ; 65(2): 181-186, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30091374

RESUMO

We explored the strategy of frozen-thawed embryo transfer (FET) in the women with advanced maternal age (AMA). We first determined the age cut-off point of AMA by retrospective analysis of pregnancy outcomes in the patients undergoing FET. The patients with AMA were divided into 3 groups including natural cycle (NC) group, controlled ovarian stimulation (COS) group, and hormone replacement therapy (HRT) group, and simultaneously were divided into 2 groups including cleavage-stage embryo transfer (CET) group and blastocyst-stage embryo transfer (BET) group. The clinical pregnancy, embryo implantation, abortion and live birth rates were compared between the 3 groups and the 2 groups, respectively. We found that in the women aged 38 years or over, the clinical pregnancy rate and live birth rate were all significantly decreased as compared with the younger than 38-year-old women (all P < 0.05), so the women aged 38 years or over were regarded as the patients with AMA in this study. In the patients with AMA, the clinical pregnancy rate and live birth rate were 22.95% and 18.03% in NC group, 23.68% and 15.79% % in COS group as well as 24.58% and 15.92% in HRT group, and there were no significant differences in the clinical pregnancy rate and live birth rate between the 3 groups. However, the clinical pregnancy rate (42.96% vs 15.87%) and embryo implantation rate (32.26% vs 9.67%) were all significantly higher in the BET group than in the CET group (all P < 0.01). We conclude that in the women aged 38 years or over, the choice of endometrial preparation protocols may depend on the individual specific conditions because the endometrial preparation protocols do not affect FET outcome, but BET can obtain better FET outcomes as compared with CET. Abbreviations: AMA: advanced maternal age; FET: frozen-thawed embryo transfer; NC: natural cycle; COS: controlled ovarian stimulation; HRT: hormone replacement therapy; CET: cleavage-stage embryo transfer; BET: blastocyst-stage embryo transfer; LH: luteinizing hormone; HCG: human chorionic gonadotropin; HMG: human menopausal gonadotropin; FSH: follicle-stimulating hormone; BMI: body mass index.


Assuntos
Transferência Embrionária , Endométrio/metabolismo , Idade Materna , Resultado da Gravidez , Adulto , Feminino , Humanos , Gravidez
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