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1.
Small ; : e1904903, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31729159

RESUMO

Cobalt oxides as efficient oxygen evolution reaction (OER) electrocatalysts have received much attention because of their rich reserves and cheap cost. There are two common cobalt oxides, Co3 O4 (spinel phase, stable but poor intrinsic activity) and CoO (rocksalt phase, active but easily be oxidatized). Constructing Co3 O4 /CoO heterophase can inherit both characteristic features of each component and form a heterophase interface facilitating charge transfer, which is believed to be an effective strategy in designing excellent electrocatalysts. Herein, an atomic arrangement engineering strategy is applied to improve electrocatalytic activity of Co3 O4 for the OER. With the presence of oxygen vacancies, cobalt atoms at tetrahedral sites in Co3 O4 can more easily diffuse into interstitial octahedral sites to form CoO phase structure as revealed by periodic density functional theory computations. The Co3 O4 /CoO spinel/rocksalt heterophase can be in situ fabricated at the atomic scale in plane. The overpotential to reach 10 mA cm-2 of Co3 O4 /CoO is 1.532 V, which is 92 mV smaller than that of Co3 O4 . Theoretical calculations confirm that the excellent electrochemical activity is corresponding to a decline in average p-state energy of adsorbed-O on the Co3 O4 /CoO heterophase interface. The reaction Gibbs energy barrier has been significantly decreased with the construction of the heterophase interface.

2.
Nature ; 574(7778): 399-403, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31619794

RESUMO

Cloud condensation nuclei (CCN) can affect cloud properties and therefore Earth's radiative balance1-3. New particle formation (NPF) from condensable vapours in the free troposphere has been suggested to contribute to CCN, especially in remote, pristine atmospheric regions4, but direct evidence is sparse, and the magnitude of this contribution is uncertain5-7. Here we use in situ aircraft measurements of vertical profiles of aerosol size distributions to present a global-scale survey of NPF occurrence. We observe intense NPF at high altitudes in tropical convective regions over both Pacific and Atlantic oceans. Together with the results of chemical-transport models, our findings indicate that NPF persists at all longitudes as a global-scale band in the tropical upper troposphere, covering about 40 per cent of Earth's surface. Furthermore, we find that this NPF in the tropical upper troposphere is a globally important source of CCN in the lower troposphere, where CCN can affect cloud properties. Our findings suggest that the production of CCN as new particles descend towards the surface is not adequately captured in global models, which tend to underestimate both the magnitude of tropical upper tropospheric NPF and the subsequent growth of new particles to CCN sizes.

3.
Bioresour Technol ; 293: 122020, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31470231

RESUMO

A lab-scale acidogenic sulfate-reducing reactor with N2 stripping was continuously operated to uncover its microbial mechanism treating highly sulfate-containing organic wastewaters. Results showed that sulfate reduction efficiency decreased with the influent COD/sulfate ratios. Microbial community analysis showed that VFA accumulation mainly caused by the predominance of fermentative bacteria including Streptococcus and Oceanotoga. Genus Desulfovibrio was the most predominant SRB and enriched at low influent COD/sulfate ratios. Although Bifidobacterium, Atopobium, Wohlfahrtiimonas, Dysgonomonas etc. had low average abundance, they were identified keystone genera by the co-occurrence network analysis. The functions of the microbial community were not insignificantly influenced by COD/sulfate ratios. All predicted functional genes involved in dissimilatory sulfate reduction reached their maximum abundances at influent COD/sulfate ratio of 1.5, while the assimilatory sulfate reduction was favored at the COD/sulfate ratio lower than 2.


Assuntos
Carbono , Desulfovibrio , Reatores Biológicos , Sulfatos , Águas Residuárias
4.
J Cell Physiol ; 234(12): 23388-23397, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31173363

RESUMO

It is well known that zinc ion (Zn2+ ) can regulate the biological activity of growth hormone (GH). However, until now, the mechanism by which Zn2+ regulates GH biological activity remains unclear. In the current study, we first performed molecular docking between Zn2+ and porcine GH (pGH) using computational biology. We then explored the effect of Zn2+ on the GH signaling ability in the cell model expressing porcine growth hormone receptor (GHR). It was found that the phosphorylation levels of Janus kinase 2, signal transducers and activators of transcription 5/3/1, and GHR increased significantly under Zn2+ treatment, indicating that Zn2+ can enhance the signaling ability of GH/GHR. On this basis, we further explored how Zn2+ regulates the biological activity of GH/GHR. The results showed that downregulation and turnover of GHR changed under Zn2+ /pGH treatment. Zn2+ enhanced the membrane residence time of pGH/GHR and delayed GHR downregulation. Further investigation showed that the internalization dynamic of pGH/GHR was changed by Zn2+ , which prolonged the residence time of pGH/GHR in the cell membrane. These factors acted together to upregulate the signaling of GH/GHR. This study lays a foundation for further exploration of the biological effects of Zn2+ on GH.

5.
J Pharm Biomed Anal ; 174: 89-103, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31158610

RESUMO

An integrated strategy based on characteristic fragment filter (CFF) supplemented by multivariate statistical analysis (MSA) for MSn chromatograms [(CFF)s MSA] was proposed for the large-scale detection of natural plant-derived ingredients in vivo. To prove the practicability of this [(CFF)s MSA] strategy, rhubarb was taken as an example. First, representative authentic standards of homologous components contained in rhubarb were chosen, from which the fragmentation rules and chemical characteristic fragments (CCFs) were proposed. Second, the metabolic pathways of the representative compounds were deciphered, and the metabolic characteristic fragments (MCFs) of each family of compounds were acquired. Third, combined with CCFs and MCFs, a CFF method was established. Finally, MSA was used to supplement the xenobiotics missed by the CFF method. In our research, 274 compounds were detected in rhubarb, and 298 ingredients were identified in vivo after oral administration. The results demonstrated that this integrated strategy could comprehensively screen for plant-derived compounds in vivo.

6.
Adv Mater ; 31(28): e1901439, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31148279

RESUMO

The design of high-efficiency non-noble bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is paramount for water splitting technologies and associated renewable energy systems. Spinel-structured oxides with rich redox properties can serve as alternative low-cost OER electrocatalysts but with poor HER performance. Here, zirconium regulation in 3D CoFe2 O4 (CoFeZr oxides) nanosheets on nickel foam, as a novel strategy inducing bifunctionality toward OER and HER for overall water splitting, is reported. It is found that the incorporation of Zr into CoFe2 O4 can tune the nanosheet morphology and electronic structure around the Co and Fe sites for optimizing adsorption energies, thus effectively enhancing the intrinsic activity of active sites. The as-synthesized 3D CoFeZr oxide nanosheet exhibits high OER activity with small overpotential, low Tafel slope, and good stability. Moreover, it shows unprecedented HER activity with a small overpotential of 104 mV at 10 mA cm-2 in alkaline media, which is better than ever reported counterparts. When employing the CoFeZr oxides nanosheets as both anode and cathode catalysts for overall water splitting, a current density of 10 mA cm-2 is achieved at the cell voltage of 1.63 V in 1.0 m KOH.

7.
Int J Nanomedicine ; 14: 1359-1383, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863066

RESUMO

Slp forms a crystalline array of proteins on the outermost envelope of bacteria and archaea with a molecular weight of 40-200 kDa. Slp can self-assemble on the surface of liposomes in a proper environment via electrostatic interactions, which could be employed to functionalize liposomes by forming Slp-coated liposomes for various applications. Among the molecular characteristics, the stability, adhesion, and immobilization of biomacromolecules are regarded as the most meaningful. Compared to plain liposomes, Slp-coated liposomes show excellent physicochemical and biological stabilities. Recently, Slp-coated liposomes were shown to specifically adhere to the gastrointestinal tract, which was attributed to the "ligand-receptor interaction" effect. Furthermore, Slp as a "bridge" can immobilize functional biomacromol-ecules on the surface of liposomes via protein fusion technology or intermolecular forces, endowing liposomes with beneficial functions. In view of these favorable features, Slp-coated liposomes are highly likely to be an ideal platform for drug delivery and biomedical uses. This review aims to provide a general framework for the structure and characteristics of Slp and the interactions between Slp and liposomes, to highlight the unique properties and drug delivery as well as the biomedical applications of the Slp-coated liposomes, and to discuss the ongoing challenges and perspectives.


Assuntos
Tecnologia Biomédica/métodos , Sistemas de Liberação de Medicamentos , Lipossomos/química , Glicoproteínas de Membrana/química , Lipossomos/ultraestrutura , Eletricidade Estática
8.
J Clin Endocrinol Metab ; 104(6): 1887-1899, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30602026

RESUMO

CONTEXT: Pegvisomant, a growth hormone receptor (GHR) antagonist, is a well-known drug that was designed to treat acromegaly. However, recent studies have indicated that the GHR is a "moonlighting" protein that may exhibit dual functions based on its localization in the plasma membrane and nucleus. In light of this finding, we explored whether pegvisomant is a potential "moonlighting" GHR antagonist. In addition, the mechanisms of the endocytosis, postendocytic sorting, and degradation of pegvisomant are not fully understood. OBJECTIVE: This study investigated whether pegvisomant is a "moonlighting" antagonist and explored the mechanisms of the endocytosis, postendocytic sorting, and degradation of pegvisomant. METHODS: Indirect immunofluorescence and Western blot coupled with pharmacological inhibitors and gene silencing (small interfering RNA) were used to explore the mechanisms of the endocytosis, postendocytic sorting, and degradation of pegvisomant. Western blot, immunohistochemistry, and indirect immunofluorescence coupled with subcellular fractionation analysis were used to determine the effect of pegvisomant on GHR's nuclear localization in vitro and in vivo. RESULTS: Here, we show that the endocytosis of pegvisomant is mainly mediated though the clathrin pathway. Further study of the postendocytic sorting of pegvisomant shows that pegvisomant enters into different types of endosomes under GHR mediation. In addition, GHR is slightly downregulated by pegvisomant; further study indicates that proteasomes and lysosomes may cooperate to regulate pegvisomant/GHR degradation. Most importantly, we show that pegvisomant inhibits the nuclear localization of GHR. CONCLUSION: Our study showed that pegvisomant is a "moonlighting" antagonist. In addition, we revealed the mechanisms of the endocytosis, postendocytic sorting, and degradation of pegvisomant.

9.
Molecules ; 23(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558163

RESUMO

Schisandra Fructus (SF) is a traditional Chinese herb used in the treatment of inflammatory disorders like hepatitis. One of the main anti-inflammatory components of SF is the lignans. However, the underlying anti-inflammatory mechanism of Schisandra Chinensis lignans (SCL) remains unclear. This study aims to investigate the effects of SCL on inflammatory mediators in lipopolysaccharide-stimulated RAW264.7 cells and explore the underlying mechanism. The production of nitric oxide (NO) was determined by Griess reaction. ELISA was used to determine cytokine levels and chemokines secretion. To estimate protein levels and enzyme activities, we employed Western blotting. Nuclear localization of NF-κB, AP-1, and IRF3 was detected using immunofluorescence analyses. The results showed that SCL significantly reduced the release of inflammatory mediators, including NO and PGE2, which may be related to down-regulation of iNOS and COX-2 expression. The production of cytokines and chemokines was suppressed by SCL treatment. SCL also decreased the phosphorylation of IKKα/ß, IκB-α, Akt, TBK1, ERK, p38, JNK, NF-κB (p65), AP-1 (c-Jun), and IRF3 in RAW264.7 macrophages activated with LPS. The nuclear protein levels and nuclear translocation of AP-1, NF-κB and IRF3 were suppressed by SCL. These results indicated that SCL suppressed the IKKα/ß/NF-κB, MAPKs/AP-1 and TBK1/IRF3 signaling pathways in LPS-stimulated RAW264.7 macrophages.


Assuntos
Lignanas/farmacologia , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Schisandra/química , Fator de Transcrição AP-1/metabolismo , Animais , Dinoprostona/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
10.
Artigo em Inglês | MEDLINE | ID: mdl-30478779

RESUMO

Start-up of membrane bioreactor under different NaCl stress was investigated in this study. Results showed that nearly 90% chemical oxygen demands and ammonia nitrogen ([Formula: see text]-N) was oxidized in none and 0.5% NaCl condition during the start-up stage. While 1% NaCl dramatically depressed the utilization of [Formula: see text]-N and about 4 weeks were required for adaption of sludge biomass to saline condition. In addition, the accumulation of nitrite high to 11.84 mg/L was observed in 1% NaCl stress, indicating the more inhibition on the activity of nitrite oxidizing bacteria. Microbial community responded to the different salinity levels. The phylum Proteobacteria and Bacteroidetes occupied over 60% in all the three MBRs. Salinity enriched the relative abundance of Maribacter, Methyloversatilis, Aeromonas and Curvibacter, while reducing the proportion of Nitrospira and Haliscomenobacter. Nitrospirae decreased sharply at 1% NaCl accounting for the accumulation of nitrite. Higher content of soluble microbial products (SMP) under saliferous MBR were released, which deteriorated the permeability of membrane module. Protein-like substances and humic substances were the main ingredients of SMP, of which the former contributed more to membrane flux decline. This study provided better understanding on the impact of salinity on the start-up of MBR.

11.
Artigo em Inglês | MEDLINE | ID: mdl-30031209

RESUMO

Eicosatrienoic acids (EETs) are a class of intermediates produced during arachidonic acid metabolism mediated by cytochrome P450 epoxygenases that exert multiple physiological effects on the nervous system. EETs promote three metabolic processes, including esterification, hydrolysis and degradation or extension. EETs are hydrolyzed by soluble epoxide hydrolase (sEH) to form corresponding diols, thereby reducing their biological activity. Strategies regulating sEH expression or activity affect EET hydrolysis and alter relative cell concentrations, thus influencing EET function. This article summarizes the metabolic pathway of eicosatrienoic acid in organisms and highlights its neuroprotective effects on the central nervous system, which include regulating neuronal excitability, increasing cerebral blood flow, inhibiting neuronal apoptosis, reducing neuroinflammation, mitigating brain injury and promoting recovery of neurological function in subjects with nervous system diseases.

12.
Biomed Chromatogr ; 32(3)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29027677

RESUMO

A rapid ultra high performance liquid chromatography tandem mass spectrometry method was developed for the simultaneous analysis of baicalin, oroxylin A-7-O-ß-d-glucoronide and chlorogenic acid in rats plasma, and applied to comparison of pharmacokinetics of Tanreqing solution between intratracheal aerosolization and intravenous injection. Results of the analytical method validation assay showed high sensitivity, accuracy and suitable recovery. Results of pharmacokinetics showed similar decline phases for baicalin, oroxylin A-7-O-ß-d-glucoronide and chlorogenic acid in two different delivery routes. The half-lives of intratracheal aerosolization and intravenous injection were 0.90 and 1.22 h for baicalin, 0.47 and 0.17 h for oroxylin A-7-O-ß-d-glucoronide and 0.22 and 0.13 h for chlorogenic acid, and this implies that compounds were retained in the lung for a relatively short time. This study was the first to provide important pharmacokinetics information for traditional Chinese medicine delivery to the lung.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas/análise , Injeção Intratimpânica , Injeções Intravenosas , Limite de Detecção , Modelos Lineares , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
13.
Int J Pharm ; 529(1-2): 227-237, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28684365

RESUMO

S-layer proteins (Slps) are crystalline arrays of protein on bacterial cell surface layers. Owning to their capability to reassemble on the surface of lipid layers, Slps have been employed to modify liposomes for various profits. But the interaction information between Slps and positively charged liposomes are destitute, especially the gastrointestinal adhesion of Slps-coating liposomes is rarely reported. In the present work, the Slps extracted from Lactobacillus helveticus were reassembled on the surface of novel positively charged liposomes composed of soybean lecithin, Eudragit®RL100 and cholesterol. The particle size and remarkable changes of Zeta potential with various Slps/lipid weight ratios were determined by dynamic light scattering and phase analysis light scattering. Significant difference in fluorescence dequenching percentage of liposomes decorated by ODA-FITC confirmed Slps self-reassemble on the surface of liposomes. A higher integrity of vesicular membrane after the addition of Triton X-100 solution demonstrated the stability enhancement of Slps-coating liposomes. Fourier transform infrared (FTIR) spectroscopy illustrated the interaction came from non-covalent bond. The mucoadhesion of Slps-coating liposomes was evaluated by the resident FITC-LP on the gastric and intestinal tract of mice at 7h and 12h after intragastrical administration, which proved that the Slps-coating improved the gastrointestinal adhesion significantly.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Lipossomos/química , Glicoproteínas de Membrana/química , Animais , Camundongos , Camundongos Endogâmicos BALB C , Octoxinol , Tamanho da Partícula
14.
Biosci Biotechnol Biochem ; 81(9): 1768-1777, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28743213

RESUMO

Oral squamous cell carcinoma (OSCC) is a disfiguring malignancy and significantly impacts the quality of patient's life. Kallikrein-related peptidase 4 (KLK4), which is closely related to cancers, is highly expressed in OSCC. To explore the biological function of KLK4 in OSCC, a KLK4-specific shRNA was used to silence its endogenous expression, and then the migration and invasion of OSCC cells were explored. Results of our study showed that silencing KLK4 inhibited the migration and invasion of OSCC cells. The protein levels of epithelial mesenchymal transition-associated markers and proteases were also altered by KLK4 silencing. Further study showed that the phosphatidylinositol 3-kinase (PI3 K)/protein kinase B (AKT) signaling pathway was involved in the function of KLK4. Treatment with a PI3 K/AKT activator reversed the migration-inhibitory effect of KLK4 shRNA. Our study suggests that KLK4 may contribute to the metastasis of OSCC through the PI3 K/AKT signaling pathway.


Assuntos
Carcinoma de Células Escamosas/patologia , Calicreínas/metabolismo , Neoplasias Bucais/patologia , Movimento Celular/genética , Ativação Enzimática , Inativação Gênica , Humanos , Células KB , Calicreínas/deficiência , Calicreínas/genética , Invasividade Neoplásica , Metástase Neoplásica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais/genética
15.
Cell Biol Int ; 41(4): 392-404, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28150891

RESUMO

Oral squamous cell carcinoma (OSCC) is a malignancy that largely impacts the quality of people's daily life. Kallikrein-related peptidase 4 (KLK4) is highly expressed in OSCC; however, its roles in OSCC cells are unclear. In the present study, the effect of KLK4 silencing on the growth of OSCC cells was investigated. Our study showed that the proliferation and colony formation of OSCC cells was inhibited by KLK4 silencing and their cell cycle was arrested. Additionally, apoptosis of OSCC cells was enhanced by KLK4 silencing, with increased protein levels of cleaved PARP, cleaved caspase-3, Bax and decreased levels of Bcl-2. KLK4 silencing inhibited the Wnt/ß-catenin signaling pathway, as evidence by decreased protein levels of Wnt1, ß-catenin, reduced GSK-3ß phosphorylation as well as decreased levels of cyclinD1 and c-myc proteins. We further showed that Wnt/ß-catenin activator reversed the effects of KLK4 silencing on the proliferation and apoptosis of OSCC cells. We concluded that KLK4 silencing inhibited the growth of OSCC cells through Wnt/ß-catenin signaling pathway, suggesting that KLK4 may become a promising therapeutic target for the treatment of OSCC.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Calicreínas/genética , Neoplasias Bucais/enzimologia , Via de Sinalização Wnt , Apoptose , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/metabolismo , Humanos , Calicreínas/metabolismo , Neoplasias Bucais/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-27404670

RESUMO

This study presented a new strategy of overall uncertainty measurement for near infrared (NIR) quantitative analysis of cryptotanshinone in tanshinone extract powders. The overall uncertainty of NIR analysis from validation data of precision, trueness and robustness study was fully investigated and discussed. Quality by design (QbD) elements, such as risk assessment and design of experiment (DOE) were utilized to organize the validation data. An "I×J×K" (series I, the number of repetitions J and level of concentrations K) full factorial design was used to calculate uncertainty from the precision and trueness data. And a 2(7-4) Plackett-Burmann matrix with four different influence factors resulted from the failure mode and effect analysis (FMEA) analysis was adapted for the robustness study. The overall uncertainty profile was introduced as a graphical decision making tool to evaluate the validity of NIR method over the predefined concentration range. In comparison with the T. Saffaj's method (Analyst, 2013, 138, 4677.) for overall uncertainty assessment, the proposed approach gave almost the same results, demonstrating that the proposed method was reasonable and valid. Moreover, the proposed method can help identify critical factors that influence the NIR prediction performance, which could be used for further optimization of the NIR analytical procedures in routine use.


Assuntos
Diterpenos de Abietano/análise , Fenantrenos/análise , Extratos Vegetais/química , Espectroscopia de Luz Próxima ao Infravermelho , Incerteza , Análise de Variância , Calibragem , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes
17.
Eur Spine J ; 26(1): 140-154, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27671279

RESUMO

PURPOSE: Spine surgery is usually associated with large amount of blood loss and blood transfusion. Excessive blood loss may cause hypotension, inadequate oxygenation of organs, necessitate allogeneic blood transfusion, and spinal epidural hematoma formation. Aprotinin, TXA, and EACA are antifibrinolytics currently offered as prophylactic agents to reduce surgery-associated blood loss. The purpose of this study was to assess the efficacy of using antifibrinolytic agents in reducing blood loss and blood transfusions in spine surgery. METHODS: PubMed, Embase, and Cochrane-controlled trials register were used to identify RCTs published before April 2015 that examined the effectiveness of intravenous aprotinin, tranexamic acid (TXA), and epsilon-aminocaproic acid (EACA) on reduction of blood loss and blood transfusions, compared with placebo in spine surgery. Randomized controlled trials reported the primary outcome that included total blood loss, intra-operative blood loss, post-operative blood loss, blood transfusion requirements, blood transfusion rate, and incidence of deep vein thrombosis. Meta-analysis was performed using the Stata12.0. Weighted mean difference with 95 % confidence intervals was used to summarize the findings across the trials for continuous outcomes. Dichotomous data were expressed as risk ratios with 95 % confidence intervals. A P < 0.05 was considered statistically significant. RESULTS: 17 studies involving 1191 patients were identified. Among them, 13 RCTs with 943 patients were included for the evaluation of total blood loss. Compared with the control group, the antifibrinolytic agents reduced total blood loss (SMD = -0.62; 95 % CI -0.75, -0.48; P = 0.000), The aprotinin group (SMD = -0.80; 95 % CI -1.22, -0.37; P = 0.938), The TXA group (SMD = -0.75; 95 % CI -0.93, -0.57; P = 0.000), and the EACA group (SMD = -0.28; 95 % CI -0.54, -0.01; P = 0.185). Thirteen RCTs with eight hundred and ninety four patients were included for the evaluation of intra-operative blood loss. Compared with the control group, the antifibrinolytic agents reduced intra-operative blood loss (SMD = -0.41; 95 % CI -0.55, -0.28; P = 0.010), The aprotinin group (SMD = -0.62; 95 % CI -0.93, -0.30; P = 0.862), The TXA group (SMD = -0.47; 95 % CI -0.64, -0.29; P = 0.005), and the EACA group (SMD = -0.16; 95 % CI -0.42, -0.11; P = 0.897). Eight RCTs with six hundred and seven patients were included for the evaluation of post-operative blood loss. Compared with the control group, the antifibrinolytic agents reduced post-operative blood loss (SMD = -0.68; 95 % CI -0.85, -0.51; P = 0.000), the aprotinin group (SMD = -0.48; 95 % CI -0.85, -0.12; P = 0.036), the TXA group (SMD = -0.80; 95 % CI -1.01, -0.59; P = 0.000), and the EACA group (SMD = -0.32; 95 % CI -0.68, -0.04; P = 0.009). Ten RCTs with seven hundred and twenty twopatients were included for the evaluation of blood transfusion. Compared with the control group, the antifibrinolytic agents reduced blood transfusion (SMD = -0.68; 95 % CI -0.85, -0.51; P = 0.000), the aprotinin group (SMD = -0.80; 95 % CI -1.22, -0.37; P = 0.938), the TXA group (SMD = -0.38; 95 % CI -0.58, -0.18; P = 0.000), and the EACA group (SMD = -0.28; 95 % CI -0.54, -0.01; P = 0.185). Twelve RCTs with eight hundred and fifteenpatients were included for the evaluation of blood transfusion rate. The transfusion rate was 35.6 % in the patients with antifibrinolytic agents and 55.2 % in the patients with placebo (RR = 0.75; 95 % CI 0.63, 0.89; P = 0.939). All studies were included for the evaluation of safety, with a total of eight thromboembolic events reported overall (two in the experimental group and six in the control group). CONCLUSIONS: The antifibrinolytic agents were able to reduce perioperative blood loss and transfusion requirements in spine surgery. TXA appeared more effective than aprotinin and EACA in reducing total blood loss, intra-operative blood loss, and blood transfusion according to the results of this analysis. The three groups in reducing the post-operative blood loss are significantly better than control groups. There was no evidence that the use of antifibrinolytic agents was a risk factor for thromboembolism in spine surgery. Further multicenter, large-sample, double-blind RCTs are required to confirm the efficacy and safety of the three antifibrinolytic agents in spine surgery.


Assuntos
Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue/estatística & dados numéricos , Hemorragia Pós-Operatória/prevenção & controle , Humanos
18.
Bioresour Technol ; 222: 470-477, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27764739

RESUMO

Performance of internal circulation anaerobic reactor (IC) treating wastewater at high organic loading rate (OLR) and role of external hydraulic circulation were evaluated. When the OLR was increased from 2.50 to 18.94kgCOD/m3/d, COD removal decreased to 85% slightly and methane production increased to 4.49L/L/d with the upflow velocity of 1.0m/h resulted from the additional hydraulic circulation. Withdrawal of external hydraulic circulation led to decrease of COD removal to lower than 60% drastically and methane production by 81%. Accumulation of volatile fatty acids caused decline of pH to below 6.0 and the shift of substrate metabolic pathway to the hybrid fermentation. In addition, both maximum methane production rate and maximum substrate degradation rate obtained from mathematical models decreased significantly. Hydrogenotrophic methanogens including Methanobacterium and Methanocorpusculum predominated in the anaerobic sludge and the shift of microbial community was also observed.


Assuntos
Reatores Biológicos/microbiologia , Consórcios Microbianos/fisiologia , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química , Análise da Demanda Biológica de Oxigênio , Ácidos Graxos Voláteis/metabolismo , Fermentação , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Cinética , Metano/metabolismo , Methanobacteriaceae/genética , Methanobacteriaceae/metabolismo , Consórcios Microbianos/genética , Modelos Teóricos , Propionatos/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos
19.
Bioresour Technol ; 216: 714-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27290667

RESUMO

Effect of elevated ammonia loading rate (ALR) and increasing salinity on the operation of membrane bioreactor (MBR) and the response of microbial community were investigated. Results showed that MBR started up with 1% NaCl stress achieved amazing nitrification performance at high salinity up to 4% when treating wastewater containing 1000mg/L NH(+)4-N. Further increasing salinity to 7% led to failure of MBR unrecoverably. Steep decline of sludge activity contributed to the extremely worse performance. High-throughput sequencing analysis showed that both ALR and salinity had selective effects on the microbial community structure. In genus level, Methyloversatilis and Maribacter were enriched during the operation. Survival of salt-resistant microbes contributed to the rising of richness and diversity at 2% and 4% NaCl stress. Analysis of amoA-gene-based cloning revealed Nitrosomonas marina are chiefly responsible for catalyzing ammonia oxidation in high ALR at high salinity stress.


Assuntos
Amônia/metabolismo , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Consórcios Microbianos/fisiologia , Eliminação de Resíduos Líquidos/instrumentação , Bactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Membranas Artificiais , Consórcios Microbianos/genética , Nitrificação , Nitrosomonas/metabolismo , Oxirredução , Salinidade , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
20.
J Pharm Sci ; 105(9): 2752-2759, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27041413

RESUMO

This study aimed to design a nanocarrier ophthalmic delivery system of muscone, a poorly water-soluble drug. The muscone thermoresponsive nanogels were self-assembled by reverse micelle → positive micelle method. Muscone was demonstrated to have uniform narrow particle size distribution in nanogel by the dynamic light scattering test. The developed nanocomposite hydrogel had a high muscone loading, and the rheology results showed that the phase transition temperature was 34.05°C. Thixotropy test indicated that the nanogel was able to resist the blinking of eyes because of the thixotropy recovery time, which is <5 s. Compared with muscone eye drops, muscone nanogels showed longer retention time on the corneal surface using fluorescent labeling technology and produced a 3.4-fold increase in apparent permeability coefficients (Papp). Draize testing showed that the developed nanogel caused no eye irritation. In vivo pharmacokinetic study indicated that the nanogel could significantly increase the bioavailability of muscone after administration compared with eye drops. These results indicate that self-assembled thermoresponsive nanogel prepared by reverse micelle → positive micelle method has potential for the ophthalmic delivery of poorly water-soluble drugs.


Assuntos
Administração Oftálmica , Cicloparafinas/administração & dosagem , Cicloparafinas/farmacocinética , Sistemas de Liberação de Medicamentos , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Disponibilidade Biológica , Piscadela , Córnea/metabolismo , Irritantes , Micelas , Soluções Oftálmicas , Tamanho da Partícula , Coelhos , Reologia , Temperatura Ambiente , Termodinâmica
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