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1.
Artigo em Inglês | MEDLINE | ID: mdl-33940137

RESUMO

OBJECTIVE: Osteoarthritis (OA) is characterized by articular cartilage loss, associated with synovial inflammation. We recently reported increased pro-inflammatory macrophages in murine post-traumatic OA (PTOA) joints, and blockade of the ubiquitin-proteasome system alleviates PTOA progression. However, the mechanisms whereby protein ubiquitination influences PTOA pathology are not well studied. We hypothesized that loss of the negative regulator of inflammation, E3 ligase Itch, in macrophages contributes to joint OA tissue damage by promoting pro-inflammatory polarization of macrophages. METHODS: Mice deficient Itch in macrophages (MΔItch) were generated by crossing Itchfl/fl mice with LysM-Cre mice. PTOA surgery was performed on global Itch knockout, Itch-/-, mice and MΔItch mice. Joint tissue damage and synovial macrophages were examined. Itch-/- cells were treated with IL-1 and pro-inflammatory polarization was determined. Expression of Itch protein and mRNA in PTOA synovium were assessed at different time points post PTOA. RESULTS: Similar to Itch-/- mice, MΔItch mice developed more severe joint damage than control mice following PTOA surgery (mean difference of OARSI score: 1.17 (95% CI 0.31∼2.03) between MΔItch and Itchfl/fl mice), accompanied by increased the inflammatory macrophage infiltration in the synovium (mean difference of % F4/80+CD86+CD36-inflammatory macrophages: 14.81 (95% CI 8.90∼20.73) between MΔItch and Itchfl/fl mice). Itch-/- macrophages exerted pro-inflammatory phenotype in response to IL-1ß treatment. Itch protein, but not mRNA levels decreased during PTOA progression. CONCLUSION: The negative regulator of inflammation, Itch, limits PTOA progression by inhibiting macrophage pro-inflammatory polarization. Itch protein degradation may contribute to PTOA pathology.

2.
Chem Asian J ; 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33945231

RESUMO

Organosilicon compounds are important reagents and synthetic intermediates that play a key role in the construction of new materials and complex products. Here we show a highly diastereoselective rhodium-catalyzed cycloisomerization of 1,6-dienes, in which the use of (EtO) 3 SiH accelerates the intramolecular cyclization reaction to afford a novel spiro-fused succinimide and pyrazolone derivatives in moderate to excellent yields as a single diastereoisomer. The proposed mechanism involves an active Rh-H species from the hydrosilane that is the H-donor in this spiro-type cycloisomerization reaction.

3.
Glob Chang Biol ; 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33934460

RESUMO

The 2015-2016 El Niño was one of the strongest on record, but its influence on the carbon balance is less clear. Using Northern Hemisphere atmospheric CO2 observations, we found both detrended atmospheric CO2 growth rate (CGR) and CO2 seasonal-cycle amplitude (SCA) of 2015-2016 were much higher than that of other El Niño events. The simultaneous high CGR and SCA were unusual, because our analysis of long-term CO2 observations at Mauna Loa revealed a significantly negative correlation between CGR and SCA. Atmospheric inversions and terrestrial ecosystem models indicate strong northern land carbon uptake during spring but substantially reduced carbon uptake (or high emissions) during early autumn, which amplified SCA but also resulted in a small anomaly in annual carbon uptake of northern ecosystems in 2015-2016. This negative ecosystem carbon uptake anomaly in early autumn was primarily due to soil water deficits and more litter decomposition caused by enhanced spring productivity. Our study demonstrates a decoupling between seasonality and annual carbon cycle balance in northern ecosystems over 2015-2016, which is unprecedented in the past five decades of El Niño events.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33864221

RESUMO

To control the spread of COVID-19, China has imposed national lockdown policies to restrict the movement of its population since the Chinese New Year of January 2020. In this study, we quantitatively analyzed the changes of pollution sources in Shanghai during the COVID-19 lockdown; a high-resolution emission inventory of typical pollution sources including stationary source, mobile source, and oil and gas storage and transportation source was established based on pollution source data from January to February 2020. The results show that the total emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter (PM), and volatile organic compounds (VOCs) were 9520.2, 37,978.6, 2796.7, and 7236.9 tons, respectively, during the study period. Affected by the COVID-19 lockdown, the mobile source experienced the largest decline. The car mileage and oil sales decreased by about 80% during the COVID-19 lockdown (P3) when compared with those during the pre-Spring Festival (P1). The number of aircraft activity decreased by approximately 50%. The impact of the COVID-19 epidemic on industries such as iron and steel and petrochemicals was less significant, while the greater impact was on coatings, chemicals, rubber, and plastic. The emissions of SO2, NOx, PM2.5, and VOCs decreased by 11%, 39%, 37%, and 47%, respectively, during P3 when compared with those during P1. The results show that the measures to control the spread of the COVID-19 epidemic made a significant contribution to emission reductions. This study may provide a reference for other countries to assess the impact of the COVID-19 epidemic on emissions and help establish regulatory actions to improve air quality.

5.
J Biomed Nanotechnol ; 17(3): 456-465, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33875080

RESUMO

Guided bone regeneration (GBR) technique is most commonly used to treat alveolar bone defect. Polylactic acid (PLA) attracts much attention to utilize as a GBR membrane because it has relatively high mechanical strength and biodegradability. However, randomized controlled trials of PLA as a GBR membrane in animals were rare. The aim of this work is to observe the efficacy of polylactic acid membrane in guiding bone regeneration in Beagle canine alveolar bone defect restoration and to compare efficacy with the collagen membrane, providing an experimental basis for further clinical use of the polylactic acid membrane. The tests of physical and chemical properties showed that the PLA membrane has well mechanical strength to maintenance the space for the new bone, and has proper aperture for the attachment of osteoblasts. Through X-ray and histopathological examination of the different time points, the bone grafting material covered with PLA membrane can form similar mature bone compared to collagen membrane ones. Meanwhile, biodegradable speed of the PLA membrane was slower. Thus, this study showed that polylactic acid membrane as synthetic biodegradable polymer was reliably effective in guiding bone regeneration of alveolar bone defects, showed the favorable osteogenic capability and forecasts well applications in bone augmentation.


Assuntos
Regeneração Óssea , Membranas Artificiais , Animais , Cães , Regeneração Tecidual Guiada Periodontal , Osteoblastos , Osteogênese , Polímeros
6.
Artigo em Inglês | MEDLINE | ID: mdl-33881999

RESUMO

This article studies the tracking control problem with a large-scale group of agents. Unlike traditional control techniques used in multiagent systems (MASs), a new type of intelligent design is needed to handle the intractable ``Curse of Dimensionality" caused by the extremely large number of agents. To address this challenge, the mean field game (MFG) theory has been embedded into reinforcement learning to advance intelligent tracking control with large-scale MAS. Specifically, MFG-based control can calculate the optimal strategy based on one unified fix-dimension probability density function (pdf) instead of high-dimensional large-scale MAS information collected from individual agents. Moreover, the approximate dynamic programming technique is adopted to generate a new type of MFG-based algorithm. Each agent has three neural networks (NNs) to approximate the solution of the mean field type control. In addition to the algorithm development, the performance of the NNs is also analyzed using the Lyapunov method. Finally, the linear and nonlinear tracking control simulations are given to evaluate the algorithm's performance.

7.
Br J Radiol ; : 20201212, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882240

RESUMO

OBJECTIVE: To establish and substantiate MRI-based radiomic models to predict the treatment response of metastatic cervical lymph node to radiochemotherapy in patients with nasopharyngeal carcinoma (NPC). METHODS: A total of 145 consecutive patients with NPC were enrolled including 102 in primary cohort and 43 in validation cohort. Metastatic lymph nodes were diagnosed according to radiologic criteria and treatment response was evaluated according to the Response Evaluation Criteria in Solid Tumors. A total of 2704 radiomic features were extracted from contrast-enhanced T1-weighted imaging (CE-T1WI) and T2-weighted imaging (T2WI) for each patient, and were selected to construct radiomic signatures for CE-T1WI, T2WI, and combined CE-T1WI and T2WI, respectively. The area under curve (AUC) of receiver operating characteristic, sensitivity, specificity, and accuracy were used to estimate the performance of these radiomic models in predicting treatment response of metastatic lymph node. RESULTS: No significant difference of AUC was found among radiomic signatures of CE-T1WI, T2WI, and combined CE-T1WI and T2WI in the primary and validation cohorts (all p > 0.05). For combined CE-T1WI and T2WI dataset, 12 features were selected to develop the radiomic signature. The AUC, sensitivity, specificity, and accuracy were 0.927 (0.878-0.975), 0.911 (0.804-0.970), 0.826 (0.686-0.922), and 0.872 (0.792-0.930) in primary cohort, and were 0.772 (0.624-0.920), 0.792 (0.578-0.929), 0.790 (0.544-0.939), and 0.791 (0.640-0.900) in validation cohort. CONCLUSION: MRI-based radiomic models were developed to predict the treatment response of metastatic cervical lymph nodes to radiochemotherapy in patients with NPC, which might facilitate individualized therapy for metastatic lymph nodes before treatment. ADVANCES IN KNOWLEDGE: Predicting the response in patients with NPC before treatment may allow more individualizing therapeutic strategy and avoid unnecessary side-effects and costs. Radiomic features extracted from metastatic cervical lymph nodes showed promising application for predicting the treatment response in NPC.

8.
J Leukoc Biol ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33884651

RESUMO

The lymphatic drainage system of the central nervous system (CNS) plays an important role in maintaining interstitial fluid balance and regulating immune responses and immune surveillance. The impaired lymphatic drainage system of the CNS might be involved in the onset and progression of various neurodegenerative diseases, neuroinflammation, and cerebrovascular diseases. A significant immune response and brain edema are observed after stroke, resulting from disrupted homeostasis in the brain. Thus, understanding the lymphatic drainage system of the CNS in stroke may lead to the development of new approaches for therapeutic interventions in the future. Here, we review recent evidence implicating the lymphatic drainage system of the CNS in stroke.

9.
Int Orthop ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33825912

RESUMO

PURPOSE: The optimal interval between staged bilateral total knee arthroplasty (STBTKA) is unclear. Studies have reported STBTKA being performed at the same admission, with a seven day interval. The safety and outcomes of patients submitted to same-admission STBTKA (SA-STBTKA) are questionable and need further investigation. METHODS: A prospective non-randomized study was performed to compare the early postoperative outcomes, systemic complications, and surgical-related complications between the first and second knees, as well as between SA-STBTKA and STBTKA groups. From July 2018 to November 2019, a total of 430 patients were recruited. Analyzed parameters included the Knee Society score (KSS), Knee Society functional score (KSFS), range of motion (ROM), Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain score, WOMAC stiffness score, and WOMAC score for daily life difficulty. RESULTS: Pre-operatively, the demographic data and functional scores were not significantly different between the two groups. The KSS, WOMAC pain score, and WOMAC stiffness score of the second knee in the STBTKA group were significantly better than those of the first knee. A total of 426 patients completed the last follow-up one  year after surgery, and the post-operative functional scores were not significantly different between the two groups and between the two knees within the same group. Before the second operation, more systemic complications were identified in the SA-STBTKA group, while the rate of surgical complication was not significantly different when compared to STBTKA patients. CONCLUSIONS: With equivalent post-operative function and a higher frequency of minor complications, SA-STBTKA should be cautiously selected as a treatment option for bilateral osteoarthritis.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33845509

RESUMO

BACKGROUND AND STUDY OBJECTIVE: Cranioplasty after microvascular decompression (MVD) is important for preventing postoperative complications such as headache. Autologous particulate bone is a common material for cranioplasty. The purpose of this study was to evaluate the effect of using autologous particulate bone to reconstruct the cranial defect produced by MVD. PATIENTS AND METHODS: Data were collected from January 2013 to December 2016 from 243 patients who underwent suboccipital retrosigmoidal craniectomy for MVD. The patients were then further divided into two groups: in the first group (from January 2013-October 2015), a cranioplasty was performed using a combination of bone dust (taken from a power drill) and particulate bone (harvested with a rongeur); in the second group (from November 2015-December 2016), the cranial defect was reconstructed using particulate bone alone. Healing of the cranial defect was observed during the follow-up. RESULTS: Early postoperative computed tomography (CT), performed during the hospital stay, revealed that the filling of the cranial defects of the first group was better than that of the second group. In addition, surgical-site infections (SSIs) occurred in 13 patients in the first group (9.92%) versus 2 patients in the second group (1.79%). The SSI rate of the first group was significantly higher than that of the second group (p < 0.05). Long-term follow-up CT demonstrated that the average reconstruction rate ((volume of the reconstruction area)/(volume of the cranial defect) × 100%) was 47.88% for the first group and 43.94% for the second group (p > 0.05). CONCLUSION: The use of autologous particulate bone to reconstruct cranial defects after MVD has a good effect and is thus a useful and valuable technique. Bone dust may result in a higher incidence of SSI.

11.
Mediators Inflamm ; 2021: 5568159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854404

RESUMO

Aims: To investigate the effect of GLP-1/GLP-1R on the polarization of macrophages in the occurrence and development of atherosclerosis. Methods: Totally, 49 patients with coronary heart disease (CHD) and 52 cases of health control (HC) were recruited, all subjects accept coronary angiography gold standard inspection. One or more major coronary arteries (LM, LAD, LCx, and RCA) stenosis degree in 50% of patients as CHD group; the rest of the stenosis less than 50% or not seen obvious stenosis are assigned to the HC group. Flow cytometry were used to detect the percentage of (CD14+) M macrophages, (CD14+CD80+) M1 macrophages, (CD14+CD206+) M2 macrophages, and their surface GLP-1R expression differences in the two groups, using BD cytokine kit to detect the levels of IL-8, IL-1ß, IL-6, IL-10, TNF, and IL-12p70. Results: GLP-1R expression on the surface of total macrophages and M2 macrophages was different between the CHD group and the HC group (P < 0.05). There was no difference in the percentage of total, M1 or M2 macrophages (P > 0.05). Concentration of IL-8 in the HC group was higher than that in the CHD group (P < 0.05). There is no significant difference in the cytokine IL-1ß, IL-6, IL-10, TNF, and IL-12p70 in the two groups (P > 0.05). After controlling for potential confounders including age, gender, smoking status (S.S.), drinking status (D.S.), HR, SBP, DBP, PP, TC, TG, HDL-C, LDL-C, GHbA1c, M, M1, M2, GLP-1R_M, GLP-1R_M1, GLP-1R_M2, IL-8, IL-1ß, IL-6, IL-10, TNF, and IL-12p70 by multiple linear regression, decreasing Gensini Score was significantly associated with increased percentage of M1 macrophage. Conclusion: GLP-1R agonist is independent of the hypoglycemic effect of T2DM and has protective effect on cardiovascular system. GLP-1R may regulate the polarization of macrophages toward M2, thus playing a protective role in the progression of coronary atherosclerosis.

12.
Plants (Basel) ; 10(4)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33804906

RESUMO

In recent years, awareness has been raised around the benefits of diversifying rootstocks, in order to enhance tree health and sustain apple fruit production under the influence of climate change. However, performances of many rootstocks under stresses remain unclear. This study aimed to set the first step towards a much-needed comprehensive evaluation on water relationships and stress responses of scion-rootstock systems for the popular apple cultivar AmbrosiaTM (Malus domestica var. Ambrosia), because its production and horticultural knowledge had been largely limited to the Malling 9 rootstock (M.9). Five rootstocks were evaluated in a greenhouse water deficit experiment and at the onset of heat stress in a field trial in Summerland, British Columbia, Canada. Multiple stress indicators of leaves and fruits were analyzed to elucidate water use strategies and drought resistance mechanisms. The rootstocks led to differences in scion vigor, and stomatal and photosynthetic characteristics. The largest semi-dwarfing Geneva 202 (G.202) demonstrated more water use and higher stress susceptibility. Large dwarfing Geneva 935 (G.935) and Malling 26 (M.26) showed more stringent stomatal control and reduced water use under stresses, typical of a drought-avoidance strategy. The smallest large dwarfing M.9NIC29® and the small dwarfing Budagovsky 9 (B.9) led to smaller and denser stomata. B.9 demonstrated the most stable water status and drought tolerance. The study suggested that scion stress responses were influenced by rootstock vigor and tree water use strategies. It implied the necessity of vigor-specific irrigation management for alleviating stresses and achieving production goals of different rootstocks.

13.
Molecules ; 26(5)2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33800313

RESUMO

Developing sustainable routes for the synthesis of zeolites is still a vital and challenging task in zeolite scientific community. One of the typical examples is sustainable synthesis of aluminosilicate EU-1 zeolite, which is not very efficient and environmental-unfriendly under hydrothermal condition due to the use of a large amount of water as solvent. Herein, we report a sustainable synthesis route for aluminosilicate EU-1 zeolite without the use of solvent for the first time. The physicochemical properties of the obtained EU-1 zeolite are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma (ICP) analysis, and solid nuclear magnetic resonance (NMR), which show the product has high crystallinity, uniform morphology, large BET surface area, and four-coordinated aluminum species. Moreover, the impact of synthesis conditions is investigated in detail. The sustainable synthesis of aluminosilicate EU-1 zeolite under solvent-free.

14.
Comput Biol Med ; 133: 104395, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33872967

RESUMO

Pathologic vertebral fractures due to metastasis can occur under normal physiologic activities, leading to pain and neurologic deficit. Prophylactic vertebroplasty is a technique used to augment vertebral strength and reduce the risk of fracture. Currently, no technique is available to objectively assess vertebral fracture risk in metastatically-involved vertebral bodies. The aim of the current study was to develop an image-based computational technique to estimate fracture force outcomes during bending. To this end, mechanical testing was performed on intact, simulated defect, PMMA-augmented, and PPF-augmented 3-level spine segments from both sexes under a compression/flexion-type loading condition. The augmentation performance of poly(methyl methacrylate) (PMMA) and poly(propylene fumarate) (PPF) were also evaluated and compared. Cylindrical defects were created in 3-level spine segments with attached posterior elements and ligaments. Using CT images of each segment, a rigidity analysis technique was developed and used for predicting fracture forces during bending. On average, PPF strengthened the segments by about 630 N, resulting in fracture forces similar to those observed in the intact and PMMA-augmented groups. Female spines fractured at about 1150 N smaller force than did male spines. Rigidity analysis, along with age, explained 66% variability in experimental outcomes. This number increased to 74% when vertebral size and age were added to the rigidity analysis as explanatory variables. Both PPF and PMMA similarly increased fracture strength to the level of intact specimens. The results suggest that PPF can be a suitable candidate for augmentation purposes and rigidity analysis can be a promising predicting tool for vertebral fracture forces.

15.
J Cell Mol Med ; 2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33811437

RESUMO

Clinical and experimental evidence indicates that tumour-associated macrophages support cancer progression. Moreover, macrophage-derived extracellular vesicles (EVs) are involved in pathogenesis of multiple cancers, yet the functions of molecular determinants in which have not been fully understood. Herein, we aim to understand whether macrophage modulates pancreatic ductal adenocarcinoma (PDAC) progression in an EV-dependent manner and the underlying mechanisms. microRNA (miR)-365 was experimentally determined to be enriched in the EVs from M2 macrophages (M2-EVs), which could be transferred into PDAC cells. Using a co-culture system, M2-EVs could enhance the proliferating, migrating and invading potentials of PDAC cells, while inhibition of miR-365 in M2-EVs could repress these malignant functions. B-cell translocation gene 2 (BTG2) was identified to be a direct target of miR-365, while the focal adhesion kinase (F/ATP)-dependent tyrosine kinase (AKT) pathway was activated by miR-365. We further demonstrated that overexpression of BTG2 could delay the progression of PDAC in vitro, whereas by impairing BTG2-mediated anti-tumour effect, M2-EV-miR-365 promoted PDAC progression. For validation, a nude mouse model of tumorigenesis was established, in which we found that targeting M2-EV-miR-365 contributed to suppression of tumour growth. Collectively, M2-EVs carry miR-365 to suppress BTG2 expression, which activated FAK/AKT pathway, thus promoting PDAC development.

16.
Biomed Res Int ; 2021: 5594081, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33860037

RESUMO

Background: The present study is aimed at providing systematic insight into the composition and expression of transfer RNA (tRNA) derivative transcription in high-grade serous ovarian cancer (HGSOC). Methods: tRNA derivative expression profiles in three pairs of HGSOC and adjacent normal ovarian tissues were conducted by tRNA-derived small RNA fragment (tRF) and tRNA half (tiRNA) sequencing. The differentially expressed tRFs and tiRNAs between HGSOC and paired adjacent normal samples were screened. The targeted genes of differentially expressed tRFs and tiRNAs were screened. The Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) of target genes of tRFs and tiRNAs were analyzed. Results: There are a total of 20 significantly upregulated and 15 significantly downregulated tRFs and tiRNAs between the cancer group and the paracarcinoma group. The upregulated tRFs and tiRNAs are mucin-type O-glycan biosynthesis, glycosphingolipid biosynthesis, the glucagon signaling pathway, the AMPK signaling pathway, maturity-onset diabetes of the young, glycosphingolipid biosynthesis, the insulin signaling pathway, insulin resistance, leukocyte transendothelial migration, starch, and sucrose metabolism. The downregulated tRFs and tiRNAs are other glycan degradation, vitamin digestion and absorption, fatty acid elongation, and biosynthesis of unsaturated fatty acids. Conclusions: There are significantly expressed tRFs and tiRNAs in HGSOC tissues, and these may provide potential diagnostic biomarkers and therapeutic targets for HGSOC.

17.
Math Biosci Eng ; 18(3): 2632-2653, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33892564

RESUMO

In developing smart cities, the implementation of social connections, collaboration, innovation, exchange of views by observing, exploiting and integrating various types of knowledge is required. The smart cities concept that employs knowledge sharing mechanism can be defined as the concept of a city that utilizes information technology to increase citizens' awareness, intelligence as well as community's participation. The knowledge dissemination via online sharing platforms has been becoming more popular in recent years, especially during the epidemic of infectious diseases. Thus, the social network and emotional analysis method based on intelligent data analysis algorithms is proposed to study the speaker relationship and comment sentiment tendency of a Chinese popular speech (knowledge dissemination) platform: YiXi. In our research, 690 speakers' information and 23,685 comments' information are collected from YiXi website as the data source. The speaker relationship network construction algorithm and emotional analysis algorithm are designed in details respectively. Experiments show that speakers who have the same profession can deliver different types of speeches, indicating that selection of YiXi platform in the invitation of speakers is diversified. In addition, overall sentiment tendency of comments on speeches seem to be slightly positive and most of them are the personal feelings according to their experience after watching speech videos instead of the direct evaluations of speech quality. The research aims to gain an insight into the popular knowledge sharing phenomenon and is expected to provide reference for knowledge dissemination platforms in order to improve the knowledge sharing environment in smart cities.

18.
J Sep Sci ; 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848379

RESUMO

In the study, high-speed counter-current chromatography was used for separation and purification of magnoflorine, spinosin, and 6‴-feruloyspinosin from Ziziphi Spinosae Semen. With n-butanol-ethyl acetate-water (2:3:5, v/v) as the optimum solvent system, about 75 mg of magnoflorine, 110 mg of spinosin, and 40 mg of 6‴-feruloyspinosin were isolated from 0.5 g of crude extract of Z. Spinosae Semen, with the purity of 95.7, 97.2, and 96.4%, respectively. The chemical structures were identified by MS and NMR spectroscopy. In addition, the antidepressant activity of the isolated components was evaluated by PC12 cells injury model and chronic unpredictable mild stress depression mouse model. The results showed that high-speed counter-current chromatography could be used to realize the one-time rapid preparation and separation of magnoflorine, spinosin, and 6‴-feruloyspinosin from Z. Spinosae Semen and compatibility of these isolated components has certain antidepressant activity.

19.
Stem Cell Res Ther ; 12(1): 208, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762018

RESUMO

BACKGROUND: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) hold great promise for regenerative medicine and in drugs screening. Despite displaying key cardiomyocyte phenotypic characteristics, they more closely resemble fetal/neonatal cardiomyocytes and are still immature; these cells mainly rely on glucose as a substrate for metabolic energy, while mature cardiomyocytes mainly employ oxidative phosphorylation of fatty acids. Studies showed that the alteration of metabolism pattern from glycolysis to oxidative phosphorylation improve the maturity of hiPSC-CMs. As a transcription factor, accumulating evidences showed the important role of NRF2 in the regulation of energy metabolism, which directly regulates the expression of mitochondrial respiratory complexes. Therefore, we hypothesized that NRF2 is involved in the maturation of hiPSC-CMs. METHODS: The morphological and functional changes related to mitochondria and cell maturation were analyzed by knock-down and activation of NRF2. RESULTS: The results showed that the inhibition of NRF2 led to the retardation of cell maturation. The activation of NRF2 leads to a more mature hiPSC-CMs phenotype, as indicated by the increase of cardiac maturation markers, sarcomere length, calcium transient dynamics, the number and fusion events of mitochondria, and mitochondrial respiration. Bioinformatics analysis showed that in addition to metabolism-related genes, NRF2 also activates the expression of myocardial ion channels. CONCLUSIONS: These findings indicated that NRF2 plays an important role in the maturation of hiPSC-CMs. The present work provides greater insights into the molecular regulation of hiPSC-CMs metabolism and theoretical basis in drug screening, disease modeling, and alternative treatment.

20.
Sci Total Environ ; 778: 146378, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33725595

RESUMO

Silicon, in its nanoscale form, has shown plant-promoting and insecticidal properties. To date, however, we lack mechanistic evidence for how nanoscale silicon influences the regulation of plant chemical defenses against herbivore attacks. To address this gap, we compared the effect of Si nanodots (NDs) and sodium silicate, a conventional silicate fertilizer, on maize (Zea mays L.) chemical defenses against the oriental armyworm (Mythimna separata, Walker) caterpillars. We found that Si NDs and sodium silicate additions, at the dose of 50 mg/L, significantly inhibited the growth of caterpillars by 53.5% and 34.2%, respectively. This increased plant resistance was associated with a 44.2% increase in the production of chlorogenic acid, as well as the expression of PAL, C4H, 4CL, C3H and HCT, core genes involved in the biosynthesis of chlorogenic acid, by 1.7, 2.4, 1.9, 1.8 and 4.5 folds, respectively. Particularly, in the presence of M. separata, physiological changes in maize plants treated with 50 mg/L Si NDs, including changes in shoot biomass, leaf nutrients (e.g., K, P, Si), and chemical defense compounds (e.g., chlorogenic acid, total phenolics), were higher than those of plants added with equivalent concentrations of conventional silicate fertilizer. Taken together, our findings indicate that Si, in nanoscale form, could replace synthetic pesticides, and be implemented for a more effective and ecologically-sound management of insect pests in maize crop farming.

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