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1.
ACS Omega ; 9(6): 6773-6786, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38371815

RESUMEN

In order to study the synergistic effect of the moisture content and pH value of aqueous solutions on coal oxidation, coal samples with different moistures were prepared by using aqueous solutions with different pH values (3, 5, 7, and 8). The CO, C2H4 production, oxygen consumption rate, and crossing point temperature parameters in the process of low-temperature oxidation of the prepared coal and raw coal samples were studied by using a low-temperature oxidation device. Thermogravimetry-derivative thermogravimetry (TG-DTG) curves of coal samples with different moistures were obtained on the basis of thermogravimetric analysis of coal by using a synchronous thermal analyzer. According to the characteristic temperature, the process of coal spontaneous combustion (CSC) can be divided into the water evaporation and desorption stage, oxygen absorption and weight gain stage, thermal decomposition and combustion stage, and burnout stage. The Coats-Redfern integral method was used to select the appropriate reaction mechanism function to calculate the apparent activation energy at different stages of the coal reaction process. The results show that the activation energy of the oxidation reaction of the coal sample with a moisture of 15% is the smallest, and the oxidation reaction is the most easy to occur. When the coal samples with a moisture of 15% were oxidized at low temperature, the CO and C2H4 emissions and oxygen consumption rates were the highest. The pH value of the aqueous solution has dual effects on CSC. When the moisture is 15%, the higher the pH value of the aqueous solution, the weaker the promotion effect on the coal oxidation process is and the lower the pH value of the aqueous solution is, the higher the production of CO and C2H4 and the oxygen consumption rate is and the earlier the crossing point temperature is reached during low-temperature oxidation of the coal sample.

2.
PLoS One ; 19(2): e0299028, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38394046

RESUMEN

Osteoclasts are crucial in the events leading to bone metastasis of lung cancer. Interleukin-17A (IL-17A) affects osteogenesis by regulating the survival of osteoclast precursors (OCPs) and is enriched in lung cancer cells. However, how factors derived from tumor cells that metastasize to bone affect osteoclastogenesis remains poorly understood. We examined whether IL-17A derived from lung cancer cells affects osteoclast differentiation by regulating OCP apoptosis. IL-17A expression was inhibited in A549 non-small cell lung cancer cells using RNA interference. Compared with conditioned medium (CM) from A549 cells (A549-CM), CM from IL-17A-deficient A549 cells (A549-si-CM) suppressed osteoclastogenesis. The mRNA expression of osteoclast-specific genes was downregulated following A549-si-CM treatment. Furthermore, A549-si-CM promoted osteoclast precursor apoptosis at an early stage of osteoclastogenesis, which was related to the promotion of caspase-3 expression by A549-si-CM during osteoclast differentiation. In vivo experiments also showed that inhibition of IL-17A expression in A549 cells reduced osteoclast activation and bone tissue destruction. Collectively, our results indicate that IL-17A deficiency inhibits lung cancer-induced osteoclast differentiation by promoting apoptosis of osteoclast precursors in the early stage of osteoclast formation and that IL-17A is a potential therapeutic target for cancer-associated bone resorption in patients with lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Diferenciación Celular/fisiología , Interleucina-17/genética , Interleucina-17/metabolismo , Neoplasias Pulmonares/patología , Osteoclastos/metabolismo , Osteogénesis/genética , Ligando RANK/metabolismo
3.
Curr Protein Pept Sci ; 25(4): 286-306, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38178676

RESUMEN

The separation of proteins in biological samples plays an essential role in the development of disease detection, drug discovery, and biological analysis. Protein imprinted polymers (PIPs) serve as a tool to capture target proteins specifically and selectively from complex media for separation purposes. Whereas conventional molecularly imprinted polymer is time-consuming in terms of incubation studies and solvent removal, magnetic particles are introduced using their magnetic properties for sedimentation and separation, resulting in saving extraction and centrifugation steps. Magnetic protein imprinted polymers (MPIPs), which combine molecularly imprinting materials with magnetic properties, have emerged as a new area of research hotspot. This review provides an overview of MPIPs for proteins, including synthesis, preparation strategies, and applications. Moreover, it also looks forward to the future directions for research in this emerging field.


Asunto(s)
Microesferas , Impresión Molecular , Polímeros Impresos Molecularmente , Proteínas , Impresión Molecular/métodos , Polímeros Impresos Molecularmente/química , Proteínas/química , Humanos , Polímeros/química
4.
J Ethnopharmacol ; 322: 117656, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38154526

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Ganoderma lucidum, a traditional edible medicinal mushroom, has been widely reported to improve liver diseases as a dietary intervention for people. Ganoderma lucidum extracts, primarily total triterpenoids (GLTTs), are one of the bioactive ingredients that have excellent beneficial effects on hepatic fibrosis. Therefore, its prevention and reversal are particularly critical due to the increasing number of patients with chronic liver diseases worldwide. AIM OF THE STUDY: The study aimed to evaluate whether GLTTs had a hepatoprotective effect against hepatic fibrosis through metabolic perturbations and gut microbiota changes and its underlying mechanisms. MATERIALS AND METHODS: The compound compositions of GLTTs were quantified, and carbon tetrachloride (CCl4)-induced hepatic fibrosis rats were used to investigate the cause of the improvement in various physiological states with GLTTs treatment, and to determine whether its consequent effect was associated with endogenous metabolites and gut microbiota using UPLC-Q-TOF-MSE metabolomics and 16S rRNA gene sequencing technology. RESULTS: GLTTs alleviated physical status, reduced liver pathological indicators, proinflammatory cytokines, and deposition of hepatic collagen fibers via regulating the NF-κB and TGF-ß1/Smads pathways. The untargeted metabolomics analysis identified 16 potential metabolites that may be the most relevant metabolites for gut microbiota dysbiosis and the therapeutic effects of GLTTs in hepatic fibrosis. Besides, although GLTTs did not significantly affect the α-diversity indexes, significant changes were observed in the composition of microflora structure. In addition, Spearman analysis revealed strong correlations between endogenous metabolites and gut microbiota g_Ruminococcus with hepatic fibrosis. CONCLUSION: GLTTs could provide a potential target for the practical design and application of novel functional food ingredients or drugs in the therapy of hepatic fibrosis.


Asunto(s)
Microbioma Gastrointestinal , Reishi , Humanos , Ratas , Animales , FN-kappa B/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Reishi/metabolismo , Ruminococcus/metabolismo , ARN Ribosómico 16S , Cirrosis Hepática/metabolismo , Comunicación , Tetracloruro de Carbono/efectos adversos
5.
PLoS One ; 18(2): e0281845, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36795736

RESUMEN

Bone is a frequent target of tumor metastasis, with high incidence rate and poor prognosis. Osteoclasts play a key role in the process of tumor bone metastasis. Interleukin-17A (IL-17A) is an inflammatory cytokine, highly expressed in a variety of tumor cells, that can alter the autophagic activity of other cells, thereby causing corresponding lesions. Previous studies have shown that low concentration IL-17A can promote osteoclastogenesis. The aim of this study was to clarify the mechanism of low concentration IL-17A promoting osteoclastogenesis by regulating autophagic activity. The results of our study showed that IL-17A could promote the differentiation of osteoclast precursors (OCPs) into osteoclasts in the presence of RANKL, and increase the mRNA levels of osteoclast-specific genes. Moreover, IL-17A increased the expression of Beclin1 by inhibiting the phosphorylation of ERK and mTOR, leading to enhanced autophagy of OCPs, accompanied by decreased OCP apoptosis. Furthermore, knockdown of Beclin1 and suppression of autophagy by 3-methyladenine (3-MA) significantly attenuated the enhanced osteoclastogenesis induced by IL-17A. In summary, these results indicate that low concentration IL-17A enhances the autophagic activity of OCPs through the ERK/mTOR/Beclin1 pathway during osteoclastogenesis, and further promotes osteoclast differentiation, suggesting that IL-17A may serve as a potential therapeutic target for cancer-related bone resorption in cancer patients.


Asunto(s)
Interleucina-17 , Osteoclastos , Autofagia , Beclina-1/genética , Beclina-1/metabolismo , Diferenciación Celular , Interleucina-17/farmacología , Interleucina-17/metabolismo , Osteoclastos/metabolismo , Ligando RANK/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
6.
Front Psychol ; 13: 890999, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35712175

RESUMEN

Many studies concerning deviant innovation behavior mainly focus on the influence of personality differences or leadership styles, and there is a lack of attention given to internal cognitive factors related to actors. Therefore, the purpose of this paper is to examine the internal mechanism of perceived support for innovation on deviant innovation behavior. A two-wave study was conducted among 393 knowledge workers from 10 knowledge-intensive enterprises in the People's Republic of China. Model 4 and Model 14 from SPSS macro PROCESS are used to test the mediating effect of innovation commitment and the moderating effect of threatened self-identity, respectively. The findings suggest that perceived support for innovation can significantly predict deviant innovation behavior; innovation commitment fully mediates the relationship between perceived support for innovation and deviant innovation behavior; public threat to self-identity plays a moderating role in the relationship between innovation commitment and deviant innovation behavior; and public threat to self-identity moderates the mediating effect of innovation commitment on perceived support for innovation and deviant innovation behavior. This study enriches the research on antecedent variables of deviant innovation behavior, and highlights the important role of situational factors on the whole mechanism.

7.
J Nurs Manag ; 30(6): 1931-1939, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35475528

RESUMEN

AIM: The aim of this study was to examine the mediating role of work-family conflict and the moderating role of job autonomy on the association between risk perception of COVID-19 and job withdrawal among Chinese nurses during the initial disease outbreak. BACKGROUND: Nurses' job withdrawal can not only reduce the quality and efficiency of care but also give rise to turnover during the COVID-19 pandemic. Thus, it is essential to clarify how and when the risk perception of COVID-19 influences the job withdrawal behaviours of nurses and to provide guidelines for reducing nurses' job withdrawal. METHODS: A two-wave study was conducted among 287 Chinese nurses from 11 COVID-19-designated hospitals during the initial outbreak of the disease from March through April 2020. Data on the risk perception of COVID-19, job autonomy and work-family conflict were collected at time 1, and 1 month later, job withdrawal data were collected at time 2. Model 4 and Model 14 from SPSS macro PROCESS were used to test the mediating effect of work-family conflict and the moderating effect of job autonomy, respectively. RESULTS: Work-family conflict mediated 60.54% of the relationship between risk perception of COVID-19 and job withdrawal. Job autonomy positively moderated the relation between work-family conflict and job withdrawal (ß = 0.12, P < 0.01). CONCLUSION: Risk perception of COVID-19 influenced nurses' job withdrawal through work-family conflict. Job autonomy exaggerated the association between work-family conflict and job withdrawal. IMPLICATIONS FOR NURSING MANAGEMENT: Managers should provide more supportive resources to help nurses cope with the risk of COVID-19 to decrease work-family conflict and job withdrawal, and they should strengthen supervision over the work processes of nurses.


Asunto(s)
COVID-19 , Enfermeras y Enfermeros , COVID-19/epidemiología , China/epidemiología , Conflicto Familiar , Humanos , Satisfacción en el Trabajo , Pandemias , Percepción , Encuestas y Cuestionarios
8.
J Pharm Biomed Anal ; 203: 114237, 2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34242946

RESUMEN

Poria cocos (Schw.) Wolf, is a fungus that is widely used as medicine and dietary supplement in China. But its action mechanism is still not very clear. In this paper, a rapid, specific and sensitive high performace liquid chromatography coupled with hybrid quadrupole - orbitrap mass sepctrometry (UPLC - Q - Orbitrap MS) method has been developed and validated to simultaneously determine of four triterpenoids including Dehydrotumulosic acid (DTA), Dehydropachymic acid (DPA), Pachymic acid (PA), Dehydrotrametenolic acid (DMA) from Poria cocos in rat plasma and tissues. The analyte was extracted from rat plasma and tissue homogenates by protein precipitation with acetonitrile using glibenclamide as the internal standard (IS). Chromatographic separation was carried out on ACQUITY UPLC BEH - C18 column (2.1 mm × 50 mm, 1.7 µm) with a mobile phase composed of acetonitrile - water (containing 1.0 mmol/L ammonium acetate) using gradient elution at a flow rate of 0.2 mL/min. Electrospray ionization (ESI -) under negative ion mode was used, and its quantization was performed with multiple reaction monitoring (MRM) mode. The method was fully validated and successfully applied to pharmacokinetics and tissue distribution study in rats after oral administration of ethanol extracts of Poria cocos. Compared with that of plasma exporsure, triterpenoids could be detected in various tissues with a relatively high degree of tissue distribution. After oral administration, the concentration orders in seven different tissues were ranked as DTA > PA > DPA > DMA in intestine and stomach, wheras DTA > DMA > PA > DPA in heart, liver, spleen, lung and kidney tissues, which is speculated that DPA, PA may be converted into DMA in vivo. In conclusion, this results may provide a material basis for study of the pharmacological actions of triterpenoids in Poria cocos.


Asunto(s)
Medicamentos Herbarios Chinos , Triterpenos , Wolfiporia , Administración Oral , Animales , China , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/análisis , Etanol , Ratas , Reproducibilidad de los Resultados , Distribución Tisular , Triterpenos/análisis
9.
Biotechnol Prog ; 34(2): 478-485, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29314781

RESUMEN

The authors conducted a three-dimensional computational fluid dynamics (CFD) simulation to calculate the flow field in the inverted frustoconical shaking bioreactor with 5 L working volume (IFSB-5L). The CFD models were established for the IFSB-5L at different operating conditions (different shaking speeds and filling volumes) and validated by comparison of the liquid height distribution in the agitated IFSB-5L. The "out of phase" operating conditions were characterized by analyzing the flow field in the IFSB-5L at different filling volumes and shaking speeds. The values of volumetric power consumption (P/VL ) and volumetric mass transfer coefficient (kL a) were determined from simulated and experimental results, respectively. Finally, the operating condition effect on P/VL and kL a was investigated. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:478-485, 2018.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula/métodos , Consumo de Oxígeno , Hidrodinámica , Oxígeno/química
10.
J Microencapsul ; 34(3): 293-298, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28425304

RESUMEN

1-Deoxynojirimycin sustained-release pellets, which exhibit known release and absorption profiles, are used for the treatment of diabetes mellitus. In this study, a fluidised bed coater was employed to prepare new, drug-loaded pellets. In the dissolution test, it was found that 1-DNJ pellets exhibited a sustained release effect after being coated with hydroxypropyl methyl cellulose phthalate-55 S. For sustained-release pellets and immediate-release pellets, there was significant difference in the mean cumulative drug concentration profile in different media evaluation. In the bioavailability study, the ratio of mean relative bioavailability of the SR pellets to the IR tablets was calculated by the DAS from the AUC0-24 h of 1-DNJ and was found to be 117.3%. This suggested that the behaviour in vivo of the 1-DNJ SR pellets was superior to the IR tablets, which indicated the designed preparation method of the 1-DNJ SR pellets was acceptable for achieving sustained release of 1-DNJ with enhanced bioavailability.


Asunto(s)
1-Desoxinojirimicina/química , Preparaciones de Acción Retardada , Comprimidos , Disponibilidad Biológica , Solubilidad
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