Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.958
Filtrar
1.
Adipocyte ; 10(1): 424-434, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34506234

RESUMO

Increasing evidence shows that immune-related genes (IRGs) play an important role in bariatric surgery (BS). We identified differentially expressed immune-related genes (DEIRGs) of adipose tissue after BS by analysing the two expression profiles of GEO (GSE59034 and GSE29409). Subsequently, enrichment analysis, GSEA and PPI networks were examined to identify the hub IRGs and related pathways. The performance of the signature was evaluated by area under the curve (AUC) of the receiver operating characteristic (ROC). CIBERSORT algorithm was used to evaluate the relative abundance of infiltrated immune cells.42 DEIRGs were found between the GSE59034 and GSE29409 datasets. The AUC of the signature was 0.904 and 0.865 in the GSE58979 and GSE48452, respectively. Interestingly, the signature also showed good performance in diagnosing non-alcoholic fatty liver disease (NAFLD) (AUC was 0.834 and 0.800, respectively). The number of neutrophils, macrophages M2, macrophages M0 and dendritic cells activated decreased significantly. After BS, the infiltration of T cells regulatory, monocytes, mast cells resting and plasma cells in adipose tissue increased. The novel proposed IRGs signature reveals the underlying immune mechanism of BS and is a promising biomarker for distinguishing the severity of NAFLD. This will provide new insights into strategies for treating obesity and NAFLD.

2.
J Colloid Interface Sci ; 607(Pt 1): 462-469, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34509728

RESUMO

Hybrid supercapacitors (HSCs) with the characteristics of high energy density, long cycle life and without altering their power density need to be developed urgently. Herein, a novel dual-ion hybrid supercapacitors (DHSCs) with Ni(OH)2 nanotube arrays (NTAs) as positive electrode and V2O5 directly grown on freestanding carbon nanotubes (CNTs) as negative electrode is assembled. In charging mechanism of DHSCs, K+ are inserted into the V2O5 negative while OH- react with Ni(OH)2 positive; during discharge, the K+ and OH- are released from V2O5 negative and Ni(OH)2 positive, respectively, and return back to the electrolyte, which is quite different from traditional metal ion or alkaline supercapacitors. Because of the merits combining dual-ion mechanism and HSCs, the DHSC displays excellent capacity retention of âˆ¼ 81.4% after 10,000 cycles, high energy density of âˆ¼ 25.4 µWh cm-2 and high power density of âˆ¼ 4.66 mW cm-2, indicating the potential applications in the further on flexible wearable electronics.

3.
BMC Infect Dis ; 21(1): 951, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521370

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) has caused a global pandemic, resulting in considerable mortality. The risk factors, clinical treatments, especially comprehensive risk models for COVID-19 death are urgently warranted. METHODS: In this retrospective study, 281 non-survivors and 712 survivors with propensity score matching by age, sex, and comorbidities were enrolled from January 13, 2020 to March 31, 2020. RESULTS: Higher SOFA, qSOFA, APACHE II and SIRS scores, hypoxia, elevated inflammatory cytokines, multi-organ dysfunction, decreased immune cell subsets, and complications were significantly associated with the higher COVID-19 death risk. In addition to traditional predictors for death risk, including APACHE II (AUC = 0.83), SIRS (AUC = 0.75), SOFA (AUC = 0.70) and qSOFA scores (AUC = 0.61), another four prediction models that included immune cells subsets (AUC = 0.90), multiple organ damage biomarkers (AUC = 0.89), complications (AUC = 0.88) and inflammatory-related indexes (AUC = 0.75) were established. Additionally, the predictive accuracy of combining these risk factors (AUC = 0.950) was also significantly higher than that of each risk group alone, which was significant for early clinical management for COVID-19. CONCLUSIONS: The potential risk factors could help to predict the clinical prognosis of COVID-19 patients at an early stage. The combined model might be more suitable for the death risk evaluation of COVID-19.

4.
Dalton Trans ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523652

RESUMO

A 3D borate-carbonate framework, GdB(OH)4CO3 (1), was synthesized. Magnetic study reveals that its MCE is up to 33.5 J kg-1 K-1 at 2 K and 2 T, due to the introduction of a long magnetic exchange path of Gd-O-B-O-Gd leading to 1 exhibiting weak magnetic interaction.

5.
Orthop Surg ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34516712

RESUMO

OBJECTIVE: To compare the clinical efficacy between robot-assisted minimally invasive transforaminal lumbar interbody fusion (robot-assisted MIS-TLIF) and traditional open TLIF surgery in the treatment of lumbar spondylolisthesis. METHODS: According to the inclusion and exclusion criteria, 48 cases with lumbar spondylolisthesis who received surgical treatment from June 2016 to December 2017 in the spinal surgery department of Beijing Jishuitan Hospital were analyzed in this study, including 23 patients who received robot-assisted MIS-TLIF and 25 patients who received traditional open TLIF surgery. The two groups were compared in terms of pedicle screw accuracy evaluated by Gertzbein-Robbins classification on postoperative computed tomography (CT), operation time, blood loss, postoperative drainage, hospitalization, time to independent ambulation, low back pain evaluated by visual analog scale (VAS), lumbar function evaluated by Oswestry Disability Index (ODI), paraspinal muscles atrophy on magnetic resonance imaging (MRI), and complications. RESULTS: Postoperative CT showed that the rate of Grade A screws in the robot-assisted MIS-TLIF group was significantly more than that in the open surgery group (χ2 = 4.698, P = 0.025). Compared with the open surgery group, the robot-assisted MIS-TLIF group had significantly less intraoperative blood loss, less postoperative drainage, shorter hospitalization, shorter time to independent ambulation, and lower VAS at 3 days post-operation (P < 0.05). However, the duration of surgery was longer. The VAS of the robot-assisted MIS-TLIF group decreased from 6.9 ± 1.8 at pre-operation to 2.1 ± 0.8 at post-operation, 1.8 ± 0.7 at 6-month follow-up and 1.6 ± 0.5 at 2-year follow-up. The VAS of the open surgery group decreased from 6.5 ± 1.7 at pre-operation to 3.7 ± 2.1 at post-operation, 2.1 ± 0.6 at 6-month follow-up and 1.9 ± 0.5 at 2-year follow-up. The ODI of the robot-assisted MIS-TLIF group decreased from 57.8% ± 8.9% at pre-operation to 18.6% ± 4.7% at post-operation, 15.7% ± 3.9% at 6-month follow-up and 14.6% ± 3.7% at 2-year follow-up. The ODI of the open surgery group decreased from 56.9% ± 8.8% at pre-operation to 20.8% ± 5.1% at post-operation, 17.3% ± 4.2% at 6-month follow-up and 16.5% ± 3.8% at 2-year follow-up. Paraspinal muscle cross-sectional area in 2-year follow-up in patients of the open surgery group decreased significantly compared to patients of robotic-assisted MIS-TLIF group (P = 0.016). CONCLUSION: In the treatment of lumbar spondylolisthesis, robot-assisted MIS-TLIF may lead to more precise pedicle screw placement, less intraoperative blood loss, less postoperative drainage, less postoperative pain, quicker recovery, and less paraspinal muscle atrophy than traditional open surgery.

6.
Brain Res ; : 147647, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34481787

RESUMO

Dendrobium nobile Lindl. alkaloid (DNLA) is effective against animal models of Alzheimer's disease. This study further examined its effect on anxiety and depression produced by chronic unpredictable stress (CUS). Rats were subjected to CUS for 42 days, followed by DNLA treatment (20 mg/kg/day, po) for 28 days. The behavioral tests, histopathology, neurotransmitters and RNA-Seq were examined. DNLA attenuated body weight loss and CUS-induced anxiety/depressive-like behaviors, as evidenced by the elevated-plus-maze test, open-field test and sucrose preference. DNLA alleviated neuronal damage and loss and increased Nissl bodies in the hippocampus CA2 region and cortex. DNLA decreased CUS-elevated 5-hydroxytryptamine, dopamine and monoamine oxidase and catechol-O-methyltransferase activities in the brain. DNLA attenuated HPA activation by decreasing adrenocorticotropic hormones and the expression of corticotropin-releasing hormone receptor-1, and increased the expression of glucocorticoid receptor in the brain. RNA-Seq revealed distinct gene expression patterns among groups. Gene ontology revealed the cell projection assembly, postsynapse and centrosome as top biological processes, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed the cAMP, cGMP-PKG, glutamatergic synapse and circadian as major pathways for DNLA effects. Using DESeq2, CUS modulated 1700 differentially expressed genes (DEGs), which were prevented or attenuated by DNLA. CUS-induced DEGs were highly correlated with the Gene Expression Omnibus (GEO) database for anxiety and depression and were ameliorated by DNLA. Taken together, DNLA attenuated anxiety/depression-like behavior and neuronal damage induced by CUS in rats. The mechanisms could be related to regulation of the monoamine neurotransmitters and the HPA axis, and modulation of gene expression in the hippocampus.

7.
Med Phys ; 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34482556

RESUMO

PURPOSE: The safety and clinical efficacy of 125 I seed-loaded stent for the treatment of portal vein tumor thrombosis (PVTT) have been shown. Accurate and fast dose calculation of the 125 I seeds with the presence of the stent is necessary for the plan optimization and evaluation. However, the dosimetric characteristics of the seed-loaded stents remain unclear and there is no fast dose calculation technique available. This paper aims to explore a fast and accurate analytical dose calculation method based on Monte Carlo (MC) dose calculation, which takes into account the effect of stent and tissue inhomogeneity. METHODS: A detailed model of the seed-loaded stent was developed using 3D modeling software and subsequently used in MC simulations to calculate the dose distribution around the stent. The dose perturbation caused by the presence of the stent was analyzed and dose perturbation kernels (DPKs) were derived and stored for future use. Then, the dose calculation method from AAPM TG-43 was adapted by integrating the DPK and appropriate inhomogeneity correction factors (ICF) to calculate dose distributions analytically. To validate the proposed method, several comparisons were performed with other methods in water phantom and voxelized CT phantoms for three patients. RESULTS: The stent has a considerable dosimetric effect reducing the dose up to 47.2% for single seed stent and 11.9%-16.1% for 16-seed stent. In a water phantom, dose distributions from MC simulations and TG-43-DP-ICF showed a good agreement with the relative error less than 3.3%. In voxelized CT phantoms, taking MC results as the reference, the relative errors of TG-43 method can be up to 33% while those of TG-43-DP-ICF method were less than 5%. For a dose matrix with 256 × 256 × 46 grid (corresponding to a phantom of 17.2 × 17.2 × 11.5 cm3 ) for 16 seeds-loaded stent, it only takes 17 seconds for TG-43-DP-ICF to compute, compared to 25 hours for the full MC calculation. CONCLUSIONS: The combination of DPK and inhomogeneity corrections is an effective approach to handle both the presence of stent and tissue heterogeneity. Exhibiting good agreement with MC calculation and computational efficiency, the proposed TG-43-DP-ICF method is adequate for dose evaluation and optimization in seed-loaded stent implantation treatment planning. This article is protected by copyright. All rights reserved.

8.
Int J Adv Manuf Technol ; : 1-36, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34465936

RESUMO

Cutting fluid has cooling and lubricating properties and is an important part of the field of metal machining. Owing to harmful additives, base oils with poor biodegradability, defects in processing methods, and unreasonable emissions of waste cutting fluids, cutting fluids have serious pollution problems, which pose challenges to global carbon emissions laws and regulations. However, the current research on cutting fluid and its circulating purification technique lacks systematic review papers to provide scientific technical guidance for actual production. In this study, the key scientific issues in the research achievements of eco-friendly cutting fluid and waste fluid treatment are clarified. First, the preparation and mechanism of organic additives are summarized, and the influence of the physical and chemical properties of vegetable base oils on lubricating properties is analyzed. Then, the process characteristics of cutting fluid reduction supply methods are systematically evaluated. Second, the treatment of oil mist and miscellaneous oil, the removal mechanism and approach of microorganisms, and the design principles of integrated recycling equipment are outlined. The conclusion is concluded that the synergistic effect of organic additives, biodegradable vegetable base oils and recycling purification effectively reduces the environmental pollution of cutting fluids. Finally, in view of the limitations of the cutting fluid and its circulating purification technique, the prospects of amino acid additive development, self-adapting jet parameter supply system, matching mechanism between processing conditions and cutting fluid are put forward, which provides the basis and support for the engineering application and development of cutting fluid and its circulating purification.

10.
Zhongguo Zhong Yao Za Zhi ; 46(15): 3859-3864, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34472260

RESUMO

This study explored the chemical constituents of the aerial part of Hypericum curvisepalum. Sixteen compounds were isolated from the 95% ethanol extract of H. curvisepalum with various chromatographic techniques, including a new prenylated phenyl polyketide, mysorenone D(1). Other compounds were mysorenone-A(2), mysorenone-C(3), mysorenone-B(4), peplidiforone A(5), 4-methoxy-3-(2-methylbut-3-en-2-yl)-6-phenyl-2H-pyran-2-one(6), hyperenone-A(7), 4-(3,3-dimethylallyl)oxy-6-phenyl-α-pyrone(8), peplidiforone B(9), elegaphenone(10), hypercohin A(11), hyperisampsin G(12), spathulenol(13), quercetin(14), ß-sitosterol(15), and ß-amyrin(16).


Assuntos
Hypericum , Benzofenonas , Quercetina
11.
Zhongguo Zhong Yao Za Zhi ; 46(15): 3934-3942, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34472270

RESUMO

The present study aimed to explore the effect of Erxian Decoction on proteomics of osteoblasts stimulated by hydrogen peroxide(H_2O_2) and its protective mechanism with the H_2O_2-induced cell model of oxidative stress. The primary osteoblasts were cultured from the skulls of newborn rats(within 24 hours) and divided into a control group, a model group, a Fosamax group, and an Erxian Decoction group. Blank serum was added in the control group and model group, and the drug-containing serum was added correspondingly to the remaining two groups. After 45 hours, H_2O_(2 )stimulation was conducted for three hours except for the control group, followed by protein extraction. Nano-LC-LTQ-Orbitrap system was used for protein detection, Protein Discovery for protein identification, and SIEVE for quantitative and qualitative analysis. Furthermore, following the blocking of PI3 K signaling pathway by LY294002(10 µmol·L~(-1)), a control group, a model group, an LY294002 group, an Erxian Decoction group, and an Erxian Decoction + LY294002 group were set up to observe the effect of Erxian Decoction on cell proliferation, alkaline phosphatase(ALP) activity, and the relative expression of BMP-2, OPG, p-Akt, p-FoxO1 of osteoblasts stimulated by H_2O_2 under LY294002 intervention. The results revealed that 78 differential proteins were discovered between the Erxian Decoction group and model group, which were involved in the regulation of PI3 K/Akt, glucagon, estrogen, insulin, and other signaling pathways. LY294002 blunted the promoting effect of Erxian Decoction on osteoblast proliferation and significantly down-regulated the expression of OPG and p-FoxO1, whereas its down-regulation on the expression of BMP-2 and p-Akt was not significant. Both LY294002 and Erxian Decoction increased the ALP activity of osteoblasts, which may be related to the cell state and the cell differentiation. The above results suggest that Erxian Decoction can protect osteoblasts stimulated by H_2O_2, with the PI3 K/Akt signaling pathway as one of the internal mechanisms.


Assuntos
Peróxido de Hidrogênio , Fosfatidilinositol 3-Quinases , Animais , Medicamentos de Ervas Chinesas , Osteoblastos/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteômica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais
12.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2813-2824, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472299

RESUMO

Squalene is widely used in pharmaceutical, nutraceutical, cosmetics and other fields because of its strong antioxidative, antibacterial and anti-tumor activities. In order to produce squalene, a gene ispA encoding farnesyl pyrophosphate synthase was overexpressed in a previously engineered Escherichia coli strain capable of efficiently producing terpenoids, resulting in a chassis strain that efficiently synthesizes triterpenoids. Through phylogenetic analysis, screening, cloning and expression of squalene synthase derived from different prokaryotes, engineered E. coli strains capable of efficiently producing squalene were obtained. Among them, squalene produced by strains harboring squalene synthase derived from Thermosynechococcus elongatus and Synechococcus lividus reached (16.5±1.4) mg/g DCW ((167.1±14.3) mg/L broth) and (12.0±1.9) mg/g DCW ((121.8±19.5) mg/L broth), respectively. Compared with the first-generation strains harboring the human-derived squalene synthase, the squalene synthase derived from T. elongatus and S. lividus remarkably increased the squalene production by 3.3 times and 2.4 times, respectively, making progress toward the cost-effective heterologous production of squalene.


Assuntos
Esqualeno , Synechococcus , Clonagem Molecular , Escherichia coli/genética , Humanos , Filogenia
13.
Nanotechnology ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479216

RESUMO

This article introduces an innovative technique for achieving a giant magnetoresistance (GMR) switch with an adjustable sensing field range. A spin-valve (SV) patterned into a strip shape is grown on a specific (110)-cut Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (PMN-PT) substrate. In the process of depositing films, a magnetic easy axis of the free layer in the SV is produced along the [001] direction (the x-axis) of the PMN-PT. This PMN-PT can produce a nonvolatile strain by using a positive voltage pulse. Accordingly, the magnetic moment of the free layer can be modulated to the y-axis by the strain-mediated magnetoelectric coupling effect produced in the SV/PMN-PT heterostructure. Furthermore, a negative voltage pulse can release the strain and revert the magnetic moment to the initial [001] direction. The effective field along the [1-10] direction produced by the nonvolatile strain can modulate the easy axis of the free layer, changing it from the x-axis to the y-axis. Therefore, large and small switching fields are achieved in a bipolar GMR switch. Furthermore, by applying positive and negative voltage pulses at appropriate moments, two asymmetrical switching field ranges are obtained. Thus, a GMR switch with four adjustable switching field ranges can be obtained. The proposed modulating model is flexible and can meet the requirements of specific and different application systems. The proposed design reveals a great potential for the application to the Internet of Things and the development of low-power and high-efficient magnetoresistive sensors.

14.
Mater Horiz ; 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494048

RESUMO

Self-healing polyurethane elastomers have been extensively studied; however, developing an eco-friendly self-healable waterborne polyurethane (WPU) with exceptional mechanical properties remains a great challenge. Herein, we report healable, and highly tough WPU elastomers with unprecedented crack tolerance by introducing the concerted interactions of strong multiple H-bonds and ionic bonds in the network. The WPU elastomer demonstrated that the microphase separation structure contributes to an ultrahigh tensile strength (≈58 MPa), super toughness (≈456 MJ m-3), and unprecedented record fracture energy (≈320 kJ m-2). Due to the dynamic reconstruction of reversible H-bonds and ionic bonds, the WPU elastomer demonstrates a robust self-healability at 50 °C, allowing complete recovery of mechanical properties. Importantly, the thermoplasticity and reprocessability of WPUs enable direct 3D printing of different objects and electrospinning of tubes, showing great potential for expanding their application scope in soft robots and artificial stents.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34481144

RESUMO

In order to characterize the molecular mechanisms by which leucine regulates carbohydrate metabolism and energy homeostasis, juvenile crucian carps (Carassius auratus gibelio var. CAS III) fed with a high carbohydrate diet were supplemented with different levels of dietary leucine: 0% (Leu0), 0.4% (Leu4), 0.8% (Leu8), 1.2% (Leu12), 1.6% (Leu16), 2.0% (Leu20), and 5.0% (Leu50). After 8 weeks, RNA sequencing was performed on samples collected from the Leu0, Leu8, Leu12 and Leu50 groups. Differentially expressed genes were then detected and analyzed. The results showed a total of 91.6 Gb of clean bases were generated. Moreover, a total of 1131, 5254, and 1539 DEGs were detected in Leu8, Leu12, and Leu50 compared with Leu0, respectively, encompassing 161 common DEGs. STEM analysis elucidated four significant clusters of DEGs that were associated with "glycerophospholipid metabolism," "glycerolipid metabolism," "PPAR signaling pathway," and "adipocytokine signaling pathway." Moreover, the mRNA expression levels of acyl-CoA synthetase long chain family member 5 (ACSL5), choline kinase beta (CHKB), cryptochrome-1 (CRY1), lon protease homolog 2, peroxisomal isoform X2 (LONP2), lipin 1 (LPIN1), membrane bound O-acyltransferase domain containing 2 (MBOAT2), phosphoenolpyruvate carboxykinase 1 (PEPCK), and uridine-cytidine kinase 2b (UCK2b) were then further investigated in all leucine treatment groups at starvation times of 0 h, 24 h, and 48 h. The results revealed that the expression levels of UCK2b and MBOAT2 were negatively correlated with the addition of leucine, whereas CHKB, LONP2, CRY1, PEPCK, and LPIN1 were positively correlated. In conclusion, dietary leucine supplementation below 1.2% enhanced carbohydrate metabolism in juvenile crucian carp fed with a high-carbohydrate diet, whereas concentrations above 2.0% is a better choice for energy homeostasis under starvation.

16.
Mol Immunol ; 139: 123-130, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481270

RESUMO

Staphylococcus aureus is majorly involved in bovine mastitis; however, it weakly induces pro-inflammatory factors in mammary gland epithelial cells. We aimed to clarify the involvement of S. aureus in other inflammation types and its relationship with inflammatory factor secretion in bovine endometritis. We used live S. aureus (LSA)- and heat-killed S. aureus (HK-SA)-treated bovine endometrial tissue in vitro. The HK-SA-treated group showed significantly higher IL-6, IL-1ß, TNF-α, CXCL1/2 and TLR2 expression than the LSA-infected group. Contrastingly, the LSA-infected group showed significantly higher PTGS2, mPGES-1, and EP4 expression than the HK-SA treated group. There was no significant between-group difference in hyaluronan-binding protein 1 expression, which suggested similar inflammatory responses. H&E results indicated that LSA and HK-SA induced shedding of endometrial gland epithelial cells. The LSA-infected group showed higher high-mobility group box 1 protein expression than the HK-SA treated groups, which indicated differences in signaling pathway activation. Further, the LSA-treated group had higher JNK and p38 MAPK levels while the HK-SA-treated group had higher IκB-α levels. There was no significant between-group difference in the ERK signaling pathway. Our findings indicate that the pathogen-associated molecular patterns (PAMPs) of S. aureus activate pro-inflammatory factor expression via the TLR2-ERK-NF-κB signaling pathway. Contrastingly, LSA induced PGE2 accumulation via the TLR2/MAPKs signaling pathway. This is the first report that S. aureus and the PAMPs of S. aureus activate different signaling pathways and that LSA mainly induce PGE2 accumulation rather than cytokine secretion.

17.
Pharmacol Res ; : 105870, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500061

RESUMO

Colorectal cancer (CRC) is one of the most common causes of cancer-related death worldwide. Nannocystin ax (NAN), a 21-membered cyclodepsipeptide initially isolated from myxobacteria of the Nannocystis genus, was found to target the eukaryotic elongation factor 1A (eEF1A). The current study was designed to evaluate the anticancer effect and underlying mechanisms of NAN with in vitro and in vivo models. Results showed that NAN induced G1 phase cell cycle arrest and caspase-independent apoptosis in HCT116 and HT29 human CRC cells. NAN significantly downregulated cyclin D1 level in a short time, but NAN did not affect the transcription level and ubiquitin-dependent degradation of cyclin D1. Furthermore, NAN treatment directly targeted eEF1A and partially decreased the synthesis of new proteins, contributing to the downregulation of cyclin D1. Besides, NAN significantly suppressed tumor growth in the zebrafish xenograft model. In conclusion, NAN triggered G1 phase cell cycle arrest through cyclin D1 downregulation and eEF1A-targeted translation inhibition and promoted caspase-independent apoptosis in CRC cells.

18.
Pest Manag Sci ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34467640

RESUMO

BACKGROUND: The coffee mealybug Planococcus lilacinus Cockerell, is an invasive pest that infests dragon fruit (Selenicereus undatus (Haworth) D.R. Hunt), that may require a phytosanitary treatment to meet quarantine requirements. In this study, vapor heat treatment was conducted to disinfest P. lilacinus on dragon fruit and the the quality of dragon fruit was evaluated thereafter. RESULTS: Adult female P. lilacinus was the most heat-tolerant stage at 47, 48 and 49 °C. The death kinetic model and probit model were used to predict LT99.9968 at the three temperatures. The treatment times predicted by the kinetic model that could effectively disinfest adult female P. lilacinus females were 120.84, 78.06, and 67.96 min at 47, 48, and 49 °C, respectively. In a confirmatory test of vapor heat treatment at 49 °C for 70 min, complete mortality was recorded for 33,195 adult females infesting in 148 dragon fruits,thus the efficacy level of disinfestation was 99.9910% at 95% confidence level. The quality of dragon fruit was generally not affected by heat treatment, fruit firmness was remarkably increased and respiration rate was significantly decreased. CONCLUSION: Our result indicates that vapor heat treatment at 49 °C for a duration of 70 min is an effective phytosanitary treatment for control of P. lilacinus on dragon fruit that minimally impacts fruit qulity.

19.
Ecotoxicol Environ Saf ; 225: 112715, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500382

RESUMO

As a natural heme protein catalyzing the oxidation of sulfides to sulfoxides without sulfone formation, chloroperoxidase (CPO) is well suited for the degradation of sulfur mustard (HD), a persistent chemical warfare agent that has been widely disposed since World War II and continuously leaks into aquatic environments. Herein, we report the first systematic investigation of CPO-catalyzed degradation of HD and the potential application of CPO in destroying chemical weapons under mild conditions. The related Michaelis-Menten parameters (Km=0.17 mM, Vmax=0.06 mM s-1 (R2 =0.935), and kcat= 2717 s-1) indicated nearly a prominent enzymatic efficiency. Under optimal conditions, 80% of HD was transformed to bis(2-chloroethyl) sulfoxide as identified by mass spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Other metabolites were also generated during the decontamination process. A plausible oxidation mechanism was proposed based on the degradation products, NMR titration experiments, and molecular dynamics simulations. CPO also promoted the degradation of other chemical weapon agents, namely, Lewisite (L) and venomous agent X (VX), thereby exhibiting a broad substrate scope. The high potential of the developed system for the decontamination of aquatic environments was demonstrated by the successful hatching of zebrafish embryos after HD degradation and the survival of zebrafish (Danio rerio, AB strain) larvae after the degradation of Agent Yellow (L+HD).

20.
Neural Netw ; 144: 75-89, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34454244

RESUMO

Whether sub-optimal local minima and saddle points exist in the highly non-convex loss landscape of deep neural networks has a great impact on the performance of optimization algorithms. Theoretically, we study in this paper the existence of non-differentiable sub-optimal local minima and saddle points for deep ReLU networks with arbitrary depth. We prove that there always exist non-differentiable saddle points in the loss surface of deep ReLU networks with squared loss or cross-entropy loss under reasonable assumptions. We also prove that deep ReLU networks with cross-entropy loss will have non-differentiable sub-optimal local minima if some outermost samples do not belong to a certain class. Experimental results on real and synthetic datasets verify our theoretical findings.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...