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1.
Eur Heart J ; 43(37): 3556-3574, 2022 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-35165707

RESUMEN

AIMS: Galectin-3, a ß-galactoside-binding lectin, is abnormally increased in cardiovascular disease. Plasma Galectin-3 receives a Class II recommendation for heart failure management and has been extensively studied for multiple cellular functions. The direct effects of Galectin-3 on platelet activation remain unclear. This study explores the direct effects of Galectin-3 on platelet activation and thrombosis. METHODS AND RESULTS: A strong positive correlation between plasma Galectin-3 concentration and platelet aggregation or whole blood thrombus formation was observed in patients with coronary artery disease (CAD). Multiple platelet function studies demonstrated that Galectin-3 directly potentiated platelet activation and in vivo thrombosis. Mechanistic studies using the Dectin-1 inhibitor, laminarin, and Dectin-1-/- mice revealed that Galectin-3 bound to and activated Dectin-1, a receptor not previously reported in platelets, to phosphorylate spleen tyrosine kinase and thus increased Ca2+ influx, protein kinase C activation, and reactive oxygen species production to regulate platelet hyperreactivity. TD139, a Galectin-3 inhibitor in a Phase II clinical trial, concentration dependently suppressed Galectin-3-potentiated platelet activation and inhibited occlusive thrombosis without exacerbating haemorrhage in ApoE-/- mice, which spontaneously developed increased plasma Galectin-3 levels. TD139 also suppressed microvascular thrombosis to protect the heart from myocardial ischaemia-reperfusion injury in ApoE-/- mice. CONCLUSION: Galectin-3 is a novel positive regulator of platelet hyperreactivity and thrombus formation in CAD. As TD139 has potent antithrombotic effects without bleeding risk, Galectin-3 inhibitors may have therapeutic advantages as potential antiplatelet drugs for patients with high plasma Galectin-3 levels.


Asunto(s)
Agregación Plaquetaria , Trombosis , Animales , Apolipoproteínas E/metabolismo , Plaquetas , Calcio/metabolismo , Fibrinolíticos/farmacología , Galectina 3/metabolismo , Galectina 3/farmacología , Lectinas Tipo C , Ratones , Ratones Noqueados para ApoE , Activación Plaquetaria , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Proteína Quinasa C , Especies Reactivas de Oxígeno/metabolismo , Quinasa Syk/metabolismo , Quinasa Syk/farmacología , Trombosis/metabolismo
2.
J Environ Manage ; 348: 119326, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37844399

RESUMEN

The soilless peat-based substrate partially solves the global soil problem in greenhouse vegetable production. However, it still produces serious N2O emissions due to the application of nutrient solutions. The pyrolysis biochar is regarded as an effective measure to reduce soil N2O emissions. However, the effect and mechanism of biochar on N2O emissions from the soilless substrate remain unknown. Therefore, this study set up six treatments by adjusting the ratio of biochar addition of peat-based substrate: 0% (0BC), 2% (2BC), 4% (4BC), 6% (6BC), 8% (8BC) and 10% (10BC) (v/v). The results showed that compared to the control treatment, N2O emissions reduced by 81%, 71%, 51%, 61%, and 75% in the 2BC, 4BC, 6BC, 8BC and 10BC treatments, respectively. In addition, lettuce yield increased by 10% and 7% in the 2BC and 4BC treatments and decreased by 0.5%, 4% and 6% in the 6BC, 8BC and 10BC treatments, respectively. Combining stable isotope technology, qPCR analysis and high-throughput sequencing, five microbial pathways of N2O production, including bacterial and archaea nitrification (BN and AN), denitrification performed by fungi, denitrifier bacteria and nitrifier bacteria (FD, DD and ND), were roughly distinguished. In addition, the extent of N2O reduction was obtained by δ18O vs.δ15NSP map. For all treatments, overall, the DD process (over 50%) was the main process of N2O production and reduction, while ND and AN processes were almost negligible (less 5%). In detail, the decrease of N2O emissions was caused by decreasing the contribution of FD in the 6BC, 8BC and 10BC treatments and reducing the contribution of BN in the 0BC and 2BC treatments. In addition, biochar addition increased the extent of N2O reduction to N2. In summary, the 2% biochar addition presented the greatest extent of N2O reduction to N2 (83%) and the lowest N2O emissions as well as the highest lettuce yields and nitrogen utilization efficiency. Therefore, 2% biochar is deemed the most optimal addition to the peat-based substrate.


Asunto(s)
Fertilizantes , Óxido Nitroso , Óxido Nitroso/metabolismo , Fertilizantes/análisis , Carbón Orgánico/metabolismo , Suelo , Lactuca/metabolismo , Bacterias/metabolismo
3.
Circulation ; 143(1): 45-61, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-32988222

RESUMEN

BACKGROUND: PCSK9 (proprotein convertase subtilisin/kexin 9), mainly secreted by the liver and released into the blood, elevates plasma low-density lipoprotein cholesterol by degrading low-density lipoprotein receptor. Pleiotropic effects of PCSK9 beyond lipid metabolism have been shown. However, the direct effects of PCSK9 on platelet activation and thrombosis, and the underlying mechanisms, as well, still remain unclear. METHODS: We detected the direct effects of PCSK9 on agonist-induced platelet aggregation, dense granule ATP release, integrin αIIbß3 activation, α-granule release, spreading, and clot retraction. These studies were complemented by in vivo analysis of FeCl3-injured mouse mesenteric arteriole thrombosis. We also investigated the underlying mechanisms. Using the myocardial infarction (MI) model, we explored the effects of PCSK9 on microvascular obstruction and infarct expansion post-MI. RESULTS: PCSK9 directly enhances agonist-induced platelet aggregation, dense granule ATP release, integrin αIIbß3 activation, P-selectin release from α-granules, spreading, and clot retraction. In line, PCSK9 enhances in vivo thrombosis in a FeCl3-injured mesenteric arteriole thrombosis mouse model, whereas PCSK9 inhibitor evolocumab ameliorates its enhancing effects. Mechanism studies revealed that PCSK9 binds to platelet CD36 and thus activates Src kinase and MAPK (mitogen-activated protein kinase)-extracellular signal-regulated kinase 5 and c-Jun N-terminal kinase, increases the generation of reactive oxygen species, and activates the p38MAPK/cytosolic phospholipase A2/cyclooxygenase-1/thromboxane A2 signaling pathways downstream of CD36 to enhance platelet activation, as well. Using CD36 knockout mice, we showed that the enhancing effects of PCSK9 on platelet activation are CD36 dependent. It is important to note that aspirin consistently abolishes the enhancing effects of PCSK9 on platelet activation and in vivo thrombosis. Last, we showed that PCSK9 activating platelet CD36 aggravates microvascular obstruction and promotes MI expansion post-MI. CONCLUSIONS: PCSK9 in plasma directly enhances platelet activation and in vivo thrombosis, and MI expansion post-MI, as well, by binding to platelet CD36 and thus activating the downstream signaling pathways. PCSK9 inhibitors or aspirin abolish the enhancing effects of PCSK9, supporting the use of aspirin in patients with high plasma PCSK9 levels in addition to PCSK9 inhibitors to prevent thrombotic complications.


Asunto(s)
Plaquetas/metabolismo , Antígenos CD36/metabolismo , Infarto del Miocardio/metabolismo , Activación Plaquetaria/fisiología , Proproteína Convertasa 9/metabolismo , Trombosis/metabolismo , Animales , Aspirina/farmacología , Aspirina/uso terapéutico , Plaquetas/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infarto del Miocardio/tratamiento farmacológico , Inhibidores de PCSK9 , Activación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/fisiología , Trombosis/tratamiento farmacológico
4.
J Thromb Thrombolysis ; 50(4): 849-857, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32285337

RESUMEN

Patients with atrial fibrillation (AF) are associated with increased thrombotic events. Our previous case-control study showed low-density lipoprotein cholesterol (LDL-C) was an independent predictor of ischemic stroke in AF patients. To investigate the risks of thrombosis in relation to LDL-C among AF patients at different stroke risks by long-time follow-up. Atrial fibrillation patients without history of thrombosis enrolled from five hospitals were classified into low-risk (LR) and high-risk (HR) group according to CHA2DS2VASc score and followed up with a median period of 26 months. Univariate and multivariate logistic regression analysis were performed in each group. The best cut-off value calculated by receiver operating characteristic (ROC) analysis was used to divide patients into low LDL-C (L-LDL) and high LDL-C (H-LDL) subgroups. Propensity score matching (PSM) and inverse probability of treatment weighted (IPTW) were utilized in both subgroups, after which Kaplan-Meier curves for thrombosis were performed. Univariate and multivariate analysis showed LDL-C was significantly related to thrombosis in LR, but less significantly in HR group. The best cut-off value was 2.155 mmol/L in LR and 2.795 mmol/L in HR group. Lower LDL-C was associated with decreased thrombosis in both groups by PSM and IPTW. Kaplan-Meier curves displayed that H-LDL subgroup was at higher thrombosis risk with significant difference at 24th month in LR patients. LDL-C independently predicts thrombosis with different cut-off values in AF patients at different risks. A stricter control of LDL-C level is necessary for thrombosis reduction in patients with lower score.


Asunto(s)
Fibrilación Atrial , LDL-Colesterol/sangre , Accidente Cerebrovascular Isquémico , Medición de Riesgo/métodos , Trombosis , Fibrilación Atrial/sangre , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , China/epidemiología , Femenino , Humanos , Accidente Cerebrovascular Isquémico/etiología , Accidente Cerebrovascular Isquémico/prevención & control , Estimación de Kaplan-Meier , Masculino , Registros Médicos/estadística & datos numéricos , Valor Predictivo de las Pruebas , Pronóstico , Factores de Riesgo , Trombosis/sangre , Trombosis/epidemiología , Trombosis/prevención & control , Tiempo
5.
J Mol Cell Cardiol ; 134: 119-130, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31299216

RESUMEN

BACKGROUND: Trimethylamine N-oxide (TMAO), a gut microbe-derived metabolite of dietary choline and other trimethylamine-containing nutrients, has been associated with poor prognosis in coronary heart disease. However, the role and underlying mechanisms of TMAO in the cardiac fibrosis after myocardial infarction (MI) remains unclear. METHODS: We used mouse MI models and primary cardiac fibroblasts cultures to study the role of TMAO in the heart and in cardiac fibroblasts. C57BL/6 mice were fed a control diet, high choline (1.2%) or/and DMB diet or a diet containing TMAO (0.12%) starting 3 weeks before MI. DMB, a structural analogue of choline, inhibited microbial TMA lyases and reduced the level of TMAO in mice. Cardiac function was measured 7 days after MI using echocardiography. One week post MI, myocardial tissues were collected to evaluate cardiac fibrosis, and blood samples were evaluated for TMAO levels. The expression of TGF-ß receptor, P-Smad2, α-SMA or collagen I in myocardial tissues and fibroblasts were analyzed by western blot or immunocytochemistry. RESULTS: We demonstrated that cardiac function and cardiac fibrosis were significantly deteriorated in mice fed either TMAO or high choline diets compared with the control diet, and DMB reversed the cardiac function damage of high choline diet (p < .05). Cardiomyocyte necrosis, apoptosis and macrophage infiltration after MI was significantly increased after treatment with TMAO or high choline diets. The size and migration of fibroblasts were increased after TMAO treatment compared with non-treated fibroblasts in vitro. Furthermore, TMAO increased TGF-ß receptor I expression, which promoted the phosphorylation of Smad2 and up-regulated the expression of α-SMA and collagen I. The ubiquitination of TGF-ßRI was decreased in neonatal mouse fibroblasts after TMAO treatment. TMAO also inhibited the expression of smurf2. Inhibition of TGF-ß1 receptor with the small molecule inhibitor SB431542 decreased TGF-ß receptor I expression, reduced the phosphorylation of Smad2, down-regulated TMAO-induced α-SMA and collagen I expression in cardiac fibroblasts. CONCLUSIONS: Cardiac function and cardiac fibrosis were significantly exacerbated in mice fed diets supplemented with either choline or TMAO, probably through accelerating the transformation of fibroblasts into myofibroblasts, indicating activation of TGF-ßRI/Smad2 pathway.


Asunto(s)
Diferenciación Celular/fisiología , Fibroblastos/metabolismo , Fibrosis/metabolismo , Microbioma Gastrointestinal/fisiología , Metilaminas/metabolismo , Miocardio/metabolismo , Miofibroblastos/metabolismo , Animales , Colágeno Tipo I/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Infarto del Miocardio/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
6.
Circulation ; 136(9): 817-833, 2017 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-28637879

RESUMEN

BACKGROUND: Platelets from patients with diabetes mellitus are hyperactive. Hyperactivated platelets may contribute to cardiovascular complications and inadequate responses to antiplatelet agents in the setting of diabetes mellitus. However, the underlying mechanism of hyperactivated platelets is not completely understood. METHODS: We measured P2Y12 expression on platelets from patients with type 2 diabetes mellitus and on platelets from rats with diabetes mellitus. We also assayed platelet P2Y12 activation by measuring cAMP and VASP phosphorylation. The antiplatelet and antithrombotic effects of AR-C78511 and cangrelor were compared in rats. Finally, we explored the role of the nuclear factor-κB pathway in regulating P2Y12 receptor expression in megakaryocytes. RESULTS: Platelet P2Y12 levels are 4-fold higher in patients with type 2 diabetes mellitus compared with healthy subjects. P2Y12 expression correlates with ADP-induced platelet aggregation (r=0.89, P<0.01). P2Y12 in platelets from patients with diabetes mellitus is constitutively activated. Although both AR-C78511, a potent P2Y12 inverse agonist, and cangrelor have similar antiplatelet efficacy on platelets from healthy subjects, AR-C78511 exhibits more powerful antiplatelet effects on diabetic platelets than cangrelor (aggregation ratio 36±3% versus 49±5%, respectively, P<0.05). Using a FeCl3-injury mesenteric arteriole thrombosis model in rats and an arteriovenous shunt thrombosis model in rats, we found that the inverse agonist AR-C78511 has greater antithrombotic effects on GK rats with diabetes mellitus than cangrelor (thrombus weight 4.9±0.3 mg versus 8.3±0.4 mg, respectively, P<0.01). We also found that a pathway involving high glucose-reactive oxygen species-nuclear factor-κB increases platelet P2Y12 receptor expression in diabetes mellitus. CONCLUSIONS: Platelet P2Y12 receptor expression is significantly increased and the receptor is constitutively activated in patients with type 2 diabetes mellitus, which contributes to platelet hyperactivity and limits antiplatelet drug efficacy in type 2 diabetes mellitus.


Asunto(s)
Plaquetas/metabolismo , Diabetes Mellitus Tipo 2/patología , Receptores Purinérgicos P2Y12/metabolismo , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Animales , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Línea Celular , Cloruros/toxicidad , AMP Cíclico/análisis , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Agonismo Inverso de Drogas , Compuestos Férricos/toxicidad , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , FN-kappa B/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Trombosis/inducido químicamente , Trombosis/tratamiento farmacológico , Trombosis/patología
7.
Cell Physiol Biochem ; 42(2): 713-728, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28618428

RESUMEN

BACKGROUND/AIMS: Mitochondrial DNA (mtDNA), acting as a newly found 'danger-associated molecular patterns' (DAMPs), is released into circulation upon tissue injury and performs as a considerable activator of inflammation and immune response. However, the role of circulating mtDNA in experimental autoimmune myocarditis (EAM) as well as Toll like receptor4 (TLR4) mediated cardiac inflammation and injury remains unknown. METHODS: A model of EAM was established in BALB/c mice by immunization with porcine cardiac myosin. Lipopolysaccharide (LPS) was used to stimulate TLR4 activation in EAM mice and H9C2 cells. RESULTS: LPS stimulation significantly aggravated cardiac inflammation and tissue injury in EAM, as demonstrated by increased myocardium inflammatory cell infiltration, and up-regulated inflammatory cytokines and troponin I(TnI) level in serum. Circulating mtDNA level was increased in EAM and TLR4 activation led to a greater elevation, which may be related to Reactive oxygen species (ROS) stress involved mtDNA damage characterized by reduced mtDNA copy number in myocardium tissue. In addition, the expression of Toll like receptor9 (TLR9), a ligand of mtDNA, was significantly up-regulated in the myocardium of EAM and EAM LPS group; meanwhile, TLR9 inhibition by ODN 2088 caused an inhibited apoptosis in LPS treated H9C2 cells. Moreover, in EAM and EAM LPS group, simultaneously giving ODN 2088 treatment significantly ameliorated cardiac inflammation and tissue injury compared with untreated group. CONCLUSION: Increased circulating mtDNA combined with upregulated TLR9 expression may corporately play a role in EAM as well as TLR4 activation mediated cardiac inflammation and injury.


Asunto(s)
Enfermedades Autoinmunes/sangre , ADN Mitocondrial/sangre , Miocarditis/sangre , Receptor Toll-Like 4/biosíntesis , Receptor Toll-Like 9/biosíntesis , Animales , Apoptosis/genética , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/patología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Lesiones Cardíacas/sangre , Lesiones Cardíacas/genética , Lesiones Cardíacas/patología , Humanos , Inflamación/sangre , Inflamación/genética , Inflamación/patología , Lipopolisacáridos/toxicidad , Ratones , Miocarditis/inducido químicamente , Miocarditis/genética , Miocarditis/patología , Miocardio/metabolismo , Miocardio/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 9/genética , Troponina I/sangre
10.
Materials (Basel) ; 17(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38591579

RESUMEN

Adsorptive atmospheric water harvesting systems (AWHs) represent an innovative approach to collecting freshwater resources from the atmosphere, with a hygroscopic agent at their core. This method has garnered significant attention due to its broad applicability, strong recycling capacity, and sustainability. It is being positioned as a key technology to address global freshwater scarcity. The core agent's hygroscopic properties play a crucial role in determining the performance of the AWHs. This article provides a comprehensive review of the latest advancements in hygroscopic agents, including their adsorption mechanisms and classifications. This study of hygroscopic agents analyzes the performance and characteristics of relevant porous material composite polymer composites and plant composites. It also evaluates the design and preparation of these materials. Aiming at the problems of low moisture adsorption and desorption difficulty of the hygroscopic agent, the factors affecting the water vapor adsorption performance and the method of enhancing the hygroscopic performance of the material are summarized and put forward. For the effect of hygroscopic agents on the volume of water catchment devices, the difference in density before and after hygroscopicity is proposed as part of the evaluation criteria. Moisture absorption per unit volume is added as a performance evaluation criterion to assess the effect of hygroscopic agents on the volume of water collection equipment. The article identifies areas that require further research and development for moisture absorbers, exploring their potential applications in other fields and anticipating the future development direction and opportunities of moisture-absorbing materials. The goal is to promote the early realization of adsorptive atmospheric water harvesting technology for large-scale industrial applications.

11.
Chemosphere ; 358: 142109, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38657692

RESUMEN

Recycling polluted water via different techniques has become one of the most feasible ways to solve the freshwater crisis. We describe a novel method to prepare reusable and efficient photothermal energy conversion materials for water purification. Using crosslinked xerogels as precursor, the porous and interconnected carboxymethylcellulose sodium-derived carbon aerogels (abbreviated as CCAs) with good hydrophilic performance and strong light absorption capability are firstly fabricated through pyrolysis. Photothermal measurement results show that CCA15 exhibit excellent solar steam generation rate of 2.31 kg m-2 h-1 with high light-to-vapor conversion efficiency of 95.9% under 1 sun illumination. In addition, the feasible application of CCA15 for efficient water purification under 1 sun irradiation using a homemade water treatment device has been demonstrated successfully. The as-prepared CCAs shown in here can be a continuable solution to mitigate the global freshwater crisis.


Asunto(s)
Carbono , Carboximetilcelulosa de Sodio , Geles , Purificación del Agua , Carboximetilcelulosa de Sodio/química , Purificación del Agua/métodos , Geles/química , Carbono/química , Luz Solar , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Porosidad
12.
Sci Total Environ ; 856(Pt 1): 159046, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36181829

RESUMEN

Soilless culture systems (SCS) play an increasing role in greenhouse vegetable production. In the SCS, soilless substrates serve as the major substitute for soil, supplying nutrients to plants but releasing greenhouse gases into the atmosphere. Remarkably, there is a serious problem of N2O emission due to excessive input of N fertilizer. However, the microbial processes of N2O production and consumption in soilless substrates have been rarely studied resulting in difficultly interpreting for its global warming potential. Therefore, these pathways from two classic soilless substrates under two irrigation patterns were investigated by stable isotope technology combined with qPCR analysis in present study. The results according to the dual isotopocule plot of δ15NSP vs. δ18O showed that the mean contribution of denitrification and the mean extent of N2O reduction of case i (Reduction-Mixing) were 26.2 and 81.2 % for the treatment of peat based substrate under drip irrigation (PD), 47.7 and 70.3 % for the treatment of coir substrate under drip irrigation (CD), 29.0 and 80.8 % for the treatment of peat based substrate under tidal irrigation (PT), and 50.8 and 47.4 % for the treatment of coir substrate under tidal irrigation (CT). These results were also further confirmed by the abundance of major functional genes including AOA amoA, nirK and nosZ. Altogether, N2O emission and its microbial processes are determined by substrate types instead of irrigation patterns. For detail, denitrification dominated in the peat based substrate and nitrification dominated in the coir substrate. Compared to the coir substrate, the peat based substrate had higher abundance of functional genes and stronger denitrification and thus generated more N2O. For the two soilless substrates, moreover, the microbiome replaced the mineral N content as the limiting factor for N2O emission. In the SCS, in summary, the two soilless substrates play an important role in tomato growth, but might suffer from inorganic nutrient surplus and microbial shortage. More importantly, the combined analysis of N2O isotopocule deltas and functional genes is a robust tool and provides reliable conclusions for clarifying the microbial processes of N2O production and consumption, thus it is also recommended for use in environments other than soilless substrates.


Asunto(s)
Desnitrificación , Óxido Nitroso , Óxido Nitroso/análisis , Microbiología del Suelo , Nitrificación , Suelo/química
13.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1745-1753, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694457

RESUMEN

Large amount of garden waste is consecutively produced in China every year. The composting with urea and microbial inoculum makes it possible to dispose garden waste in large quantities. However, composting accompanies with serious nitrogen loss and environmental problems. The biogas slurry contains considerable nitrogen nutrients and microorganisms, which theoretically could be used as alternative to urea and bacteria to reduce nitrogen loss, respectively. We set up three treatments of biogas slurry + garden waste (GB), biogas slurry + garden waste + urea (GBU), and biogas slurry + garden waste + urea + microbial inoculum (GBUM) to investigate the decomposition, nitrogen conversion and nitrogen loss in the co-composting process. The results showed that the high tempe-rature period of GB treatment was longer and more stable compared to that of GBU and GBUM treatments. The pH and EC value of GB treatment would benefit composting process and generated products with the highest germination index (GI) (221.8%). In addition, NH3 and N2O emission rates in the GB treatment were 2.59 mg·kg-1·d-1 and 3.65 µg·kg-1·d-1, respectively, being 99.0% and 50.0% lower than that in the GBU treatment and 99.4% and 40.7% lower than that in the GBUM treatment. The results of δ18O vs. δ15NSP dual isotopocule plots approach analysis showed that the GB and GBU treatments were dominated by denitrification, and that the contribution of denitrification was higher in the GB treatment. In contrast, the GBUM treatment was dominated by nitrification. The degree of N2O reduction in GB treatment (83.7%) was higher than the other two treatments. It was clear that GB treatment had the best maturity and lowest nitrogen loss in all treatments by enhancing the N2O reduction process during denitrification to reduce N2O emission. In conclusion, the biogas slurry and garden wastes could be directly co-composted without the limitation of C/N and microbial addition. The co-composting method could protect the environment and save resources leading to the recycling of waste in actual production.


Asunto(s)
Compostaje , Jardines , Biocombustibles , Nitrógeno , Urea
14.
Sci Total Environ ; 803: 150082, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34525774

RESUMEN

The microalgal-bacterial symbiotic (MBS) system shows great advantages in the synchronous implementation of wastewater treatment and nutrient recovery. To enhance the understanding of different MBS systems, this review summarizes reported MBS systems and proposes three patterns according to the living state of microalgae and bacteria. They are free microalgal-bacterial (FMB) system, attached microalgal-bacterial (AMB) system and bioflocculated microalgal-bacterial (BMB) system. Compared with the other two patterns, BMB system shows the advantages of microalgal biomass harvesting and application. To further understand the microalgal-bacterial partnerships in the bioflocculation of BMB system, this review discusses bioflocs characteristics, extracellular polymeric substances (EPS) properties and production, and the effect of microalgae/bacteria ratio and microalgal strains on the formation of bioflocculation. Microalgal biomass production and application are important for BMB system development in the future. Food processing wastewater characterized by high biodegradability and low toxicity should be conducive for microalgal cultivation. In addition, exogenous addition of functional bacteria for nutrient removal and bioflocculation formation would be a crucial research direction to facilitate the large-scale application of BMB system.


Asunto(s)
Microalgas , Bacterias , Biomasa , Simbiosis , Aguas Residuales
15.
Artículo en Inglés | MEDLINE | ID: mdl-35564722

RESUMEN

Peat is a nonrenewable resource that we are using at alarming rates. Development of peat alternative from pruning waste (PW) could be a cost- and environment-friendly way of disposal. Steam explosion (SE) is a commonly used pretreatment of lignocellulosic biomass, but its impact on the properties of PW as a growing substrate is largely unknown. To address this issue, PW was treated using five SE temperatures (160, 175, 190, 205 and 220 °C) and three retention times (1, 3 and 5 min) and evaluated for key traits of growing substrate. Results indicate that bulk density, total porosity, EC, total carbon, and concentration of phytotoxins including phenol, flavonoid, and alkaloid significantly increased or tended to increase with increasing temperature and/or retention time. A reversed trend was observed for water-holding capacity, pH, content of hemicellulose and lignin, and germination index. Cation exchange capacity and total N showed minimal response to SE. Steam explosion had inconsistent impacts on acid soluble nutrients. Phytotoxicity was a major factor limiting the use of SE-treated PW as growing substrate. Higher pretreatment severity led to higher phytotoxicity but also facilitated subsequent phytotoxicity removal by torrefaction. Pruning waste treated by SE and torrefaction under certain conditions may be used as peat substitute for up to 40% (v/v).


Asunto(s)
Alcaloides , Vapor , Biomasa , Lignina/química , Plantas , Suelo
16.
Artículo en Inglés | MEDLINE | ID: mdl-36141889

RESUMEN

Much previous research has indicated most composts of pruning waste are characterized by potential phytotoxicity, it is highly correlated with the chemical compounds of raw materials. Cinnamomum camphora, a common kind of pruning waste in Southeast Asia and East Asia, is characterized by intense bioactivities due to complex chemical components. This study investigated the potential phytotoxicity of C. camphora pruning waste in light of germination and higher plant growth. C. camphora extracted from leaves completely inhibited seed germination and still showed suppression of root elongation at an extremely low dosage. C. camphora extract also displayed significant inhibition of nutrient absorption in tomato seedlings, including moisture, available nutrients (N, P and K) and key microelements (Fe, Mn, Zn and S). The gene expression of aquaporins and transporters of nitrate and phosphate was significantly up-regulated in roots. This could be regarded as a positive response to C. camphora extract for enhancing nutrient absorption. Moreover, the severe damage to the plasma membrane in roots caused by C. camphora extract might seriously affect nutrient absorption. Camphor is the main component of the C. camphora extract that may induce the phytotoxicity of plasma membrane damage, resulting in the inhibition of nutrient absorption and low biomass accumulation. This study provided a new understanding of the ecotoxicological effects of C. camphora pruning waste, indicating that the harmless disposal of pruning waste requires much attention and exploration in the future.


Asunto(s)
Cinnamomum camphora , Alcanfor/metabolismo , Cinnamomum camphora/química , Cinnamomum camphora/genética , Cinnamomum camphora/metabolismo , Germinación , Nitratos/análisis , Fosfatos/análisis , Extractos Vegetales/metabolismo , Extractos Vegetales/toxicidad , Hojas de la Planta/química
17.
Oncol Lett ; 21(5): 384, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33777207

RESUMEN

Gastrointestinal schwannoma is a rare, slow-growing and benign tumor that mostly originates in the Auerbach myenteric nerve plexus in the gastrointestinal tract. The clinical manifestations may be associated with the location, size, differentiation type, and degree of malignancy of the tumor. Endoscopy, ultrasound and imaging examinations serve an important auxiliary role in the clinical identification, diagnosis and differential diagnosis of lesions; assessment of risk; and preparation for surgery. S-100 positivity is a hallmark of schwannoma. CD34, CD117, discovered on GIST-1, P53, ALK, ß-catenin, smooth muscle actin and Desmin negativity are helpful for the identification of other gastrointestinal stromal tumors. Surgical removal of the tumor is the main treatment for schwannoma. Benign gastrointestinal schwannoma has a good prognosis without recurrence and metastasis; malignant transformation is extremely rare and has a poor prognosis.

18.
Bioresour Technol ; 331: 124955, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33774570

RESUMEN

Superheated steam (SHS) has been used as a carrier gas for pressurized steam torrefaction, steam explosion or pyrolysis, but is barely used as a heat source. However, SHS is superior in thermal capacity and heat transfer coefficient resulting in even heating and fast heating rates. Therefore, this work applied SHS as the sole heat source for torrefaction at ambient pressure. A setup was specially designed and capable of heating wood shavings at a rate >120 °C•min-1. Solid products were analyzed in many aspects and demonstrated the enhanced organics conversion owing to SHS torrefaction. Torrefied biomass was comparable to slow pyrolysis char in fuel quality and superior to that of conventional torrefactions. Moreover, SHS torrefaction was super-timesaving. A coal-like product (HHV of 27.84 MJ•kg-1) was achieved in only 15 min at 350 °C. Overall, SHS torrefaction boosted biomass densification and gaveriseto greater production efficiency.


Asunto(s)
Calor , Vapor , Biomasa , Pirólisis , Temperatura , Madera
19.
Bioresour Technol ; 342: 125929, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34537532

RESUMEN

Superheated steam (SHS) was capable of fast and uniformly torrefying heavily loaded biomass. This work detailedly investigated the torrefied biomass in terms of fuel property and combustion behavior. The reactor chamber (300 ml) was fully loaded with pinewood pellets (160 g). Overall residence times were 20, 40 and 60 min (including preheating and holding periods) under 225, 275 and 325 °C. Biomass was estimated by elements, TG, FTIR, HHV, fuel property, combustion and pyrolysis behaviors, combustion kinetics and moisture reabsorption. Holding period as short as 2 min at 325 °C with a heating rate of 15 °C‧min-1 was found to enhance energy density by 45% and generated homogeneous coal-like products with HHV of 26.76 MJ‧kg-1. Fixed carbon content increased to 64.84 wt%. The combustion activation energy increased to 79.66 kJ‧mol-1. Combustion indices and behaviors indicated that torrefied biomass had benign characteristics either for co-firing or as fuel. All suggests good potential of SHS torrefaction to obtain fuel alternatives.


Asunto(s)
Pinus , Vapor , Biomasa , Carbón Mineral , Pirólisis , Temperatura
20.
J Immunol Res ; 2021: 5556659, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33987448

RESUMEN

Camptothecin (CPT) is a cytotoxic quinoline alkaloid isolated from the bark and branches of the Chinese tree Camptotheca acuminata. CPT inhibits topoisomerase I. It possesses various antitumor activities and is mainly used in the treatment of colon, ovarian, liver, and bone cancers as well as leukemia. CPT inhibits the expressions of inflammatory genes and can prevent death from chronic inflammation. Therefore, we investigated the effect of CPT treatment in ulcerative colitis (UC) using DSS-induced UC mouse model; after that, we explored its potential mechanisms. Here, we found that CPT exerted protection on DSS-induced UC in rats. In addition, the administration prominently reduced the disease activity index as well as colon length of the model rats and remarkably reduced the inflammatory cytokines. Further, CPT significantly reduced several vital proinflammatory proteins in LPS-induced RAW264.7 cells. In summary, our findings demonstrate that CPT is hopefully to act as a therapeutic agent for UC.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Colon/efectos de los fármacos , Sulfato de Dextran/farmacología , Mucosa Intestinal/efectos de los fármacos , Animales , Camptotecina , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Colon/inmunología , Colon/patología , Citocinas/metabolismo , Sulfato de Dextran/administración & dosificación , Sulfato de Dextran/uso terapéutico , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Humanos , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Lipopolisacáridos/inmunología , Ratones , Ratones Endogámicos C57BL , Células RAW 264.7
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