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1.
PLoS One ; 14(10): e0223218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31574112

RESUMO

OBJECTIVE: To identify risk factors associated with unfavorable outcomes in children with IgA vasculitis with nephritis (Henoch-Schonlein purpura nephritis)(IgA-VN). METHODS: PubMed, Embase, and Web of Science databases were searched for studies, published in English through February 2019. The data were extracted to perform pooled analysis, heterogeneity testing, subgroup analysis, sensitivity analysis, and publication bias analysis. RESULTS: This meta-analysis showed that, older age at onset (WMD 1.77, 95% CI 0.35-3.18, p = 0.014), lower glomerular filtration rate (GFR; WMD -23.93, 95% CI -33.78- -14.09, p<0.0001), initial renal manifestations with nephrotic syndrome (OR 1.74, 95% CI 1.12-2.70, p = 0.013), with nephritic-nephrotic syndrome (OR 4.55, 95% CI 2.89-7.15, p<0.0001) and renal biopsy with crescentic nephritis (International Study of Kidney Disease in Children [ISKDC] grades III-V) (OR 3.85, 95% CI 2.37-6.28, p<0.0001) were significant risk factors associated with poor outcomes in IgA-VN, whereas initial clinical features with hematuria (OR 0.33, 95% CI 0.16-0.69, p = 0.003) and mild proteinuria±hematuria (OR 0.46, 95% CI 0.28-0.75, p<0.0001) were associated with progression to good outcomes. By contrast, gender, hypertension and initial renal manifestations of acute nephritic syndrome were not significantly associated with poor outcomes in IgA-VN. CONCLUSION: This meta-analysis showed that older age at onset, lower GFR, initial renal features of nephrotic syndrome and nephritic-nephrotic syndrome and renal biopsy with crescentic nephritis (ISKDC grades III-V) were predictive of poor prognosis in children with IgA-VN.

2.
BMJ Open ; 9(8): e028717, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31467050

RESUMO

INTRODUCTION: Idiopathic nephrotic syndrome (INS) is the most common glomerulopathy that results in childhood chronic kidney disease in China, but the relationships between different clinical phenotypes and immunological genetic variants observed in patients with INS are ambiguous and have not been well studied. A cohort study combined with whole exome sequencing might further identify the effects of immunological genetic variants on clinical phenotypes and treatment outcomes. METHODS AND ANALYSIS: We describe a 3 year prospective observational single-centre cohort study to be conducted in the Children's Hospital of Chongqing Medical University in China. This study will recruit and investigate 336 patients with childhood-onset INS presenting with different clinical phenotypes. Whole exome sequencing will be conducted when patients progress to a confirmed clinical phenotype during follow-up. Relevant clinical and epidemiological data, as well as conventional specimens, will be collected at study entry and 1 month, 3 months, 6 months, 1 year, 2 years and 3 years after disease onset. After this cohort is generated, the immunological genetic variants of steroid-sensitive nephrotic syndrome without frequent relapse, steroid-resistant nephrotic syndrome and steroid-dependent/frequent relapse nephrotic syndrome will be evaluated. ETHICS AND DISSEMINATION: The study protocol is approved by Ethics Committee of Children's Hospital of Chongqing Medical University (reference number 2018-140). The results will be disseminated through peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: ChiCTR1800019795.

3.
Mol Immunol ; 114: 162-170, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352232

RESUMO

Clinically, most patients with primary nephrotic syndrome (PNS) have low serum IgG levels, which is an important factor in infection and in PNS relapse.To some extent, the mechanisms involved remain largely unknown. Here, we aimed to investigate the pathogenesis of the decreased IgG levels in PNS. Peripheral blood was collected from patients with PNS and closely age- and sex-matched healthy individuals. The frequency, phenotype and molecular function of different circulating B cell and T follicular helper cell (TFH) subsets were examined by flow cytometry. The function of the CD40/CD40 L interaction in immunoglobulin class-switch recombination (CSR) was evaluated by assessing the induction of activation-induced deaminase (AID) expression with CD40 L stimulation. We revealed an increase in the levels of circulating total plasmablasts, plasma cells and mature-naive B cells and a decrease in the levels of germinal centre-like B cells and CD19+IgG+ B cells in PNS. In addition, although the expression of CD86 on the surface of B cells and the expression of the inducible costimulator (ICOS) on the surface of TFH cells both were increased, the expression of CD40 L on the surface of TFH cells was decreased. Moreover, upon stimulation with CD40 L in vitro, the mRNA expression of AID in peripheral blood mononuclear cells (PBMCs) was decreased in patients with PNS compared with that in healthy controls. Our results indicate that the immunoglobulin CSR of B cells was partly dysfunctional and provide insights into the potential involvement of impaired TFH cell-dependent B cell responses in the pathogenesis of low IgG levels through downregulating CD40 L expression on TFH cells in PNS.

4.
Bioresour Technol ; 289: 121729, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323723

RESUMO

The micropores present in ZSM-5 are beneficial to the production of aromatic compounds in biomass catalytic pyrolysis, although the small pore size leads to severe coke deposition on the catalyst. In this study, a micro-mesoporous structured ZSM-5 zeolite catalyst was synthesized and modified with green templates (sucrose, cellulose, and starch) to introduce additional mesopores. It was found that the catalysts modified using the sucrose and cellulose templates only exhibited a slight increase in their micropore volumes, while the mesopore volume of ZSM-ST (modified with the starch template) reached up to 0.359 cm3/g. This increase promoted the cracking of bulky oxygenates and suppressed the polymerization reaction on the ZSM-5 surface, thereby producing a greater number of aromatic products. Moreover, the benzene, toluene, and xylene (BTX) yields exhibited a positive correlation with the catalyst mesopore volume, with the highest BTX yield of 91.84 mg/g being obtained with 10% starch addition.


Assuntos
Pirólise , Xilenos , Biomassa , Catálise , Tolueno
5.
Bioresour Technol ; 287: 121444, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31096102

RESUMO

To understand the role of Fe on biomass pyrolysis, Fe-catalyzed biomass pyrolysis in a fixed-bed reactor was investigated. It was found that the introduction of Fe increased the yields of gases and solid char while decreasing the yield of liquid oil. With increasing temperature, Hydrogen content in gaseous products obtained in the presence of Fe increased, while that of CH4 decreased. In the case of liquid oil, the introduction of Fe promoted the formation of ketones and acids at 400-600 °C, and these species became dominant (67.51%) at 700-800 °C. Finally, solid char obtained in the presence of Fe at 700-800 °C featured a larger pore volume, specific surface area, and graphitization degree, and was characterized by a mesoporous structure with narrow pores size distribution (∼5.3 nm).


Assuntos
Temperatura Alta , Pirólise , Biomassa , Gases , Temperatura Ambiente
6.
Bioresour Technol ; 287: 121493, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31112930

RESUMO

In this study, the reaction mechanism for the pyrolysis of cellulose, hemicellulose and lignin in the presence of CaO was examined using TG-FTIR and PY-GC/MS. Results indicated that, at low temperature (400-600 °C), in addition to H2O and CO2, acids and phenols from hemicellulose pyrolysis, sugars from cellulose pyrolysis and phenols from lignin pyrolysis would react with CaO. While, at elevated temperature (600 °C-800 °C), the catalytic effect of CaO was more obvious. In detail, in hemicellulose pyrolysis, CaO promoted the catalytic decarbonylation of ketones to form CO, and meanwhile, the formation of hydrocarbons was enhanced. For cellulose pyrolysis, the presence of CaO enhanced the ring-opening and dehydration reactions of sugars, and thus promoted the formation of light organics. As to the pyrolysis of lignin, CaO addition favored the radical reactions and thus increased the yield of CH4. In addition, those monohydric phenols with lower carbon numbers increased.


Assuntos
Temperatura Alta , Pirólise , Biomassa , Lignina
7.
Medicine (Baltimore) ; 98(22): e15927, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31145359

RESUMO

INTRODUCTION: A network meta-analysis was conducted to regard the effects of available immunosuppressive medications in pediatric frequently-relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome (SDNS). METHODS: We reviewed systematically 26 randomized controlled trials (1311 patients) that compared any of the following immunosuppressive agents to placebo/nontreatment (P/NT) or another drug for FRNS/SDNS treatment in children. RESULTS: The main outcomes were efficacy and acceptability. At the 6-month, cyclophosphamide, chlorambucil, levamisole, and rituximab had better efficacy than P/NT (odds ratio [OR]: 0.09, 0.03, 0.28, and 0.07, respectively); cyclophosphamide was significantly more effective than azathioprine and chlorambucil. At 12 months, cyclophosphamide, chlorambucil, cyclosporine, levamisole, and rituximab had better efficacy than P/NT (0.10, 0.03, 0.10, 0.23, and 0.07, respectively); Chlorambucil were found to be more efficacious than levamisole and MMF (0.12 and 0.09, respectively). At 24 months, cyclophosphamide, chlorambucil, and levamisole had better efficacy than P/NT (0.09, 0.04, and 0.03, respectively); cyclophosphamide had better efficacy than cyclosporine and vincristine (0.17 and 0.39, respectively). CONCLUSION: No significant differences in acceptability were found. Our results suggest that cyclophosphamide may be preferred initially in children with FRSN/SDNS, chlorambucil, and rituximab may be acceptable medications for patients with FRSN/SDNS. Long-term follow-up trials focused on gonadal toxicity and limitation of maximum dosage of cyclophosphamide should been carried out.


Assuntos
Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Síndrome Nefrótica/tratamento farmacológico , Adolescente , Azatioprina/uso terapêutico , Criança , Pré-Escolar , Clorambucila/uso terapêutico , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Lactente , Levamisol/uso terapêutico , Masculino , Meta-Análise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Rituximab/uso terapêutico , Prevenção Secundária/métodos , Resultado do Tratamento
8.
BMC Pediatr ; 19(1): 158, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101091

RESUMO

BACKGROUND: There is limited information available regarding the clinical management of intravenous immunoglobulin-resistant Kawasaki disease (KD). We aimed to evaluate the optimal treatment options for patients with refractory KD by presenting an indirect-comparison meta-analysis. METHODS: PubMed, EMBASE, Web of Science, and the Cochrane Database were searched on August 31, 2018. Unpublished studies were also searched in ProQuest Dissertations & Theses and through manual retrieval strategies. Randomized concurrent controlled trials (RCTs), high-quality non-randomized concurrent controlled trials (non-RCTs), and retrospective studies associated with AEs were included. The quality of all eligible studies was assessed using Cochrane collaboration's tool and non-randomized study guidelines. Risk ratios (RR) with 95% confidence intervals (CIs) for dichotomous outcomes were estimated in our analysis. GRADE profiler 3.6.1 was used to assess the evidence profile. RESULTS: Twelve studies involving 372 immunoglobulin-resistant KD patients were identified and analyzed. Neither infliximab nor intravenous pulse methylprednisolone (IVMP) was significantly more effective than second IVIG infusion with respect to lowering coronary artery lesions (CALs) (infliximab, 0.85, 0.43-1.69; IVMP, 0.99, 0.52-1.88) and treatment resistance (infliximab, 0.43, 0.21-0.89; IVMP, 1.16, 0.33-4.13). No significant differences were found between infliximab and IVMP in the incidence rate of CALs (0.70, 0.27-1.81), the treatment resistance (0.37, 0.09-1.60), the rates of coronary artery aneurysm (4.13, 0.38-45.22) and the coronary artery dilatation (0.45, 0.10-1.99). Furthermore, compared with second IVIG infusion, both infliximab and IVMP showed significant effectiveness in antipyretic effects (infliximab, 1.52, 1.16-1.99; IVMP, 1.29, 0.77-2.15). However, Infliximab was noninferior to IVMP on antipyretic effects (1.18, 0.66-2.15). IVMP treatment showed significant association with fewer AEs than second IVIG infusion (0.49, 0.26-0.94) and infliximab (2.34, 1.07-5.09). No significant differences were noted between infliximab treatment and second IVIG infusion (1.06, 0.69-1.63). CONCLUSIONS: Infliximab, IVMP, and second IVIG infusion showed no significant differences in the cardioprotective effect or the rate of treatment resistance. Infliximab and IVMP treatment were more effective than second IVIG infusion regarding antipyretic effects. IVMP treatment may have an advantage due to its lower total rate of AEs associated with drug infusion. TRIAL REGISTRATION: The study has been registered on PROSPERO ( CRD42016039693 ).

9.
Bioresour Technol ; 281: 309-317, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30826517

RESUMO

Untreated corn stalk (CS), deionized water washed CS (WCS), aqueous phase bio-oil washed CS (LCS), and 5% acetic acid washed CS (CCS) were torrefied at 230, 260, and 290 °C. The influences of washing, torrefaction, and combined washing-torrefaction pretreatments on corn stalk pyrolysis were investigated. The combined pretreatments, especially aqueous phase bio-oil washing-torrefaction improved fuel properties of pretreated samples largely by increasing their volatile and hydrogen contents. Absorption peaks of O-H and CO groups in combined pretreatment samples increased when torrefaction temperature increased. In addition, CO, H2, and CH4 contents of pyrolysis gas increased, while CO2 decreased after combined pretreatments. The bio-oil yields from WCS290, LCS290, and CCS290 increased by 134.04%, 127.66%, and 129.79% respectively, compared with that from CS290. Similarly, their relative sugar contents (rich in levoglucosan) increased to 36.63%, 45.89%, and 52.34%, respectively. Aqueous phase oil washing-torrefaction is a promising pretreatment and acetic acid plays the most important role.


Assuntos
Óleos Vegetais/química , Polifenóis/química , Zea mays/química , Temperatura Alta , Pirólise , Água
10.
Bioresour Technol ; 279: 252-261, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30735935

RESUMO

The effects of wood vinegar (WVG) on microbial activity and communities of activated sludge were investigated in a sequencing batch reactor (SBR) process. Results showed that the optimal WVG concentration was 4 µL/L when the pollutants removal efficiency and microbial activity were promoted by a WVG dilution factor of 1000. WVG could reduce the increase in microbial species richness, which led to a more notable variety of microbial species diversity. The enhanced microbial activity and communities were addressed to the promotion of 7 main classes of microbes in Proteobacteria, Bacteroidetes, Acidobacteria, and Nitrospirae phyla. The growth of ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), and main genera of denitrifying bacteria (DNB), phosphorus-accumulating organisms (PAOs), and glycogen-accumulating organisms (GAOs) could be promoted by WVG, which improved the sewage treatment effectiveness in a SBR.


Assuntos
Biomassa , Microbiota , Esgotos/microbiologia , Ácido Acético , Reatores Biológicos/microbiologia , Desnitrificação , Metanol , Fósforo/metabolismo , Pirólise
11.
Bioresour Technol ; 278: 248-254, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708327

RESUMO

Biomass catalytic pyrolysis with various metals (Zn, Fe, Ca, Ce and La) modified ZSM-5 catalysts were analyzed, in order to investigate the relationship between the physicochemical properties of catalysts and the benzene, toluene and xylene (BTX) products. Results revealed that the BTX products were positively correlated with the strong acid site contents of the catalysts. Appropriate amount (0.5-4 wt%) of loaded Zn species increased the strong acid site contents of the catalysts as well as BTX yields, and the highest yield of BTX was observed under Zn loading amount of 2 wt%. While excessive metal loading amount (10 wt%) decreased both the acidity and the physical properties of the catalyst, resulting in poor diffusion of reactants and products in the channel and decreased the BTX yield. It is recommended that ZSM-5 catalyst with higher strong acid site content and pore volume should be used for BTX production.


Assuntos
Benzeno/química , Tolueno/química , Xilenos/química , Zeolitas/química , Biomassa , Cálcio/química , Catálise , Fenômenos Químicos , Lantânio/química , Metais Pesados/química , Pirólise
12.
Bioresour Technol ; 280: 260-268, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30776652

RESUMO

The effect of chemical activation and NH3 modification on activated carbons (ACs) was explored via two contrasting bamboo pyrolysis strategies involving either two steps (activation followed by nitrogen doping in NH3 atmosphere) or one step (activation in NH3 atmosphere) with several chemical activating reagents (KOH, K2CO3, and KOH + K2CO3). The ACs produced by the two-step method showed relatively smaller specific surface areas (∼90% micropores) and lower nitrogen contents. From the one-step method, the ACs had larger pore diameters with about 90% small mesopores (2-3.5 nm). Due to a promotion effect with the KOH + K2CO3 combination, the AC attained the greatest surface area (2417 m2 g-1) and highest nitrogen content (3.89 wt%), endowing the highest capacitance (175 F g-1). The balance between surface area and nitrogen content recommends KOH + K2CO3 activation via the one-step method as the best choice for achieving both greener production process and better pore structure.


Assuntos
Amônia/química , Biomassa , Carbono/química , Nitrogênio/química , Carvão Vegetal/química , Capacitância Elétrica , Porosidade
13.
Bioresour Technol ; 275: 53-60, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576914

RESUMO

In this study, biochar obtained from pyrolysis of woody shavings at 550 °C was reacted with iron ore in N2 to investigate its inert chemical looping conversion properties, including the gas products conversion kinetics and structural evolution process. Results found that both the release of CO and CO2 could be divided into rapid release stage and stable chemical looping reaction stage with activation energies of 17.69 and 45.65 kJ/mol, respectively. During the chemical looping process, the reaction reactivity of biochar reduced gradually with the amorphous char structure turning into fused ring structure and finally into graphite crystal structure. Simultaneously, Fe2O3 was reduced into Fe3O4, FeO and Fe. This work highlighted the chemical conversion of biochar using natural iron ore as oxygen carrier in inert N2 atmosphere from the common in-situ gasification chemical looping process using CO2/H2O as agent.


Assuntos
Carvão Vegetal/química , Ferro/química , Oxigênio/química , Dióxido de Carbono/química , Cinética
14.
Biosci Rep ; 39(1)2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30559146

RESUMO

Plenty of studies have investigated the effect of methionine synthase (MTR) A2756G polymorphism on risk of developing pediatric acute lymphoblastic leukemia (ALL), but the available results were inconsistent. Therefore, a meta-analysis was conducted to derive a more precise estimation of the association between MTR A2756G polymorphism and genetic susceptibility to pediatric ALL. The PubMed, Embase, Google Scholar, Web of Science, ScienceDirect, Wanfang Databases and China National Knowledge Infrastructure were systematically searched to identify all the previous published studies exploring the relationship between MTR A2756G polymorphism and pediatric ALL risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were applied to evaluate the strength of association. Sensitivity analysis and publication bias were also systematically assessed. This meta-analysis finally included ten available studies with 3224 ALL cases and 4077 matched controls. The results showed that there was significant association between MTR A2756G polymorphism and risk of pediatric ALL in overall population (AG vs. AA: OR = 1.13, 95%CI = 1.02-1.26, P = 0.02; AG+GG vs. AA: OR = 1.13, 95%CI = 1.02-1.25, P = 0.01; G allele vs. A allele: OR = 1.10, 95%CI = 1.01-1.20, P = 0.03). In the stratification analyses by ethnicity, quality score and control source, significant association was found in Caucasians, population-based designed studies and studies assigned as high quality. In conclusion, this meta-analysis suggests that MTR A2756G polymorphism may influence the development risk of pediatric ALL in Caucasians. Future large scale and well-designed studies are required to validate our findings.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , Criança , Grupo com Ancestrais do Continente Europeu , Feminino , Expressão Gênica , Estudos de Associação Genética , Humanos , Masculino , Razão de Chances , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/etnologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Risco
15.
Bioresour Technol ; 274: 25-32, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30500760

RESUMO

The effects of wood vinegar (WVG) on extracellular polymeric substances (EPS), and flocculation, sedimentation and dewatering performances of activated sludge were investigated in sequencing batch reactor (SBR) process. Results showed that polysaccharide (PS) and DNA were accounted for the largest and smallest proportion of EPS, respectively. With WVG injection, productions of soluble EPS (S-EPS), loosely bound EPS (LB-EPS), tightly bound EPS (TB-EPS), protein (PN), PS, and DNA were significantly increased. The optimal WVG concentration was found as 4 µl/l. The effects of WVG on different types of EPS followed an order of LB-EPS > TB-EPS > S-EPS. According to batch and long-term SBR operations, WVG could increase the biomass amount of activated sludge, which was beneficial to improve sewage treatment efficiencies. However, WVG showed negative impact on flocculation, sedimentation, and dewatering performance of activated sludge.

16.
Bioresour Technol ; 274: 145-152, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30502605

RESUMO

To improve the quality of the oil produced from microalgae, the co-pyrolysis of low-density polyethylene (LDPE) and Nannochloropsis sp. (NS) in a fixed bed reactor was investigated at different mixing ratios. Co-pyrolysis improved the gas yield, and the lower heating value of the gas products increased obviously with an increase in the LDPE amount. Furthermore, co-pyrolysis promoted the generation of CH4 and C2+, especially C2H4, with the maximum C2+ yield (84.86 mL/g) obtained with 75% LDPE. Meanwhile, the amounts of oxygenous and nitrogenous compounds in the liquid products decreased rapidly with LDPE addition. The aliphatic hydrocarbon content of the liquid products increased from 22.63% for NS pyrolysis to 77.4% with 25% LDPE. During co-pyrolysis with LDPE, O tended to evolve as H2O and CO (rather than as CO2 for NS pyrolysis) and N was more likely to be released into gas products, which enhanced the quality of the pyrolysis oil.

17.
Bioresour Technol ; 273: 153-158, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30439633

RESUMO

Firstly, the operating conditions were screened for biomass pyrolysis in a fixed bed with respect to higher oil yield. A temperature of 600 °C with an N2 flow of 80 ml/min exhibited the highest bio-oil yield. Then, the catalytic pyrolysis of biomass with various catalysts (Al2O3, CaO, MgO, CuO, Fe2O3, NiO, ZnO, ZrO2, TiO2, HZSM-5 and MCM-41) was studied to identify the selective deoxygenation method with respect to improve bio-oil quality with smaller drop in bio-oil yield. With the addition of CaO, the oxygen was mainly removed in the form of CO2, while, in other cases, more oxygen was removed in the form of H2O. Furthermore, more decarboxylation or less dehydration is better for the balance between yield and deoxygenation amount, and the preferred decarboxylation would lead to a higher pH and lower moisture content of bio-oil.

18.
Bioresour Technol ; 273: 77-85, 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30415072

RESUMO

In this study, the effects of a macroporous catalyst (CaO), mesoporous catalyst (MCM-41), and microporous catalysts (ZSM-5 and SAPO-34) on the production of light olefins and aromatics from cellulose catalytic fast pyrolysis were investigated in a dual-catalyst fixed bed reactor. Further the fractional catalytic pyrolysis of MCM-41 or CaO with ZSM-5 or SAPO-34 was explored. The results showed that ZSM-5 was the most efficient catalyst for the formation of light olefins and aromatics followed by MCM-41, CaO and SAPO-34, and no aromatics were found with SAPO-34 only. Moreover, 15% CaO combined 85% ZSM-5 produced the highest yield of light olefins (5.59%) and aromatic (13.42%). The addition of CaO and MCM-41 promoted the selectivity of C2H4 and decreased the production of naphthalene.

19.
Med Sci Monit ; 24: 6832-6839, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30258045

RESUMO

BACKGROUND CD36 plays a critical role in many sterile inflammatory diseases, including type 2 diabetes mellitus, atherosclerosis, and primary nephrotic syndrome. This study investigated whether CD36 activates the nucleotide-binding domain leucine-rich repeat-containing family, pyrin domain-containing-3 (NLRP3) inflammasome and promotes podocytes apoptosis in primary nephrotic syndrome. MATERIAL AND METHODS The mouse podocyte cell line MPC5 was used as a model. mRNA and protein expression of CD36 and NLRP3 was quantified by real-time PCR and Western blotting, respectively. Levels of caspase-1 activity and total cholesterol were determined using commercial kits. Intracellular lipid droplets were detected by Oil Red O staining. CD36 expression was also examined in nephrotic mouse kidney tissue by immunohistochemistry and immunofluorescence. Intracellular lipid droplet was examined by Oil Red O staining. RESULTS CD36 expression was increased in nephrotic mouse kidney tissue. Treatment with interleukin-1b increased expression of CD36 and total cholesterol in MPC5 cells. Moreover, this treatment increased expression of NLRP3 and the percentage of apoptotic cells, both of which were inhibited by co-treatment with an anti-CD36 antibody. CONCLUSIONS CD36 might play an important role in podocyte apoptosis by activating the NLRP3 inflammasome in primary nephrotic syndrome.

20.
Bioresour Technol ; 270: 189-197, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30218935

RESUMO

The pyrolysis behavior of Chinese chestnut and Jatropha curcas shells (CNS and JCS, respectively) were investigated to determine the optimum operating temperature for biomass pyrolytic polygeneration systems. At low temperatures (250-450 °C), CO2 was the main component of the pyrolytic gas, and high acidity oil was obtained. When the temperature increased to 550-650 °C, phenol-enriched oil and high LHV biochar (∼26 MJ/kg) were obtained; H2 and CO yields increased. At high temperatures (750-950 °C), heavy-oil and high LHV pyrolytic gas (∼15 MJ/m3) were obtained. Meanwhile, the biochar showed a highly condensed aromatic ring system and low H/C (∼0.1) and O/C (∼0.05) ratios. CNS and JCS biochars showed different tendencies with regard to their structure evolution. An economic analysis was performed, which suggested that the optimum operating temperatures were 450 °C for CNS and 350 °C for JCS.

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