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1.
BMC Plant Biol ; 24(1): 561, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877454

RESUMO

BACKGROUND: Somatic embryogenesis (SE) is recognized as a promising technology for plant vegetative propagation. Although previous studies have identified some key regulators involved in the SE process in plant, our knowledge about the molecular changes in the SE process and key regulators associated with high embryogenic potential is still poor, especially in the important fiber and energy source tree - eucalyptus. RESULTS: In this study, we analyzed the transcriptome and proteome profiles of E. camaldulensis (with high embryogenic potential) and E. grandis x urophylla (with low embryogenic potential) in SE process: callus induction and development. A total of 12,121 differentially expressed genes (DEGs) and 3,922 differentially expressed proteins (DEPs) were identified in the SE of the two eucalyptus species. Integration analysis identified 1,353 (131 to 546) DEGs/DEPs shared by the two eucalyptus species in the SE process, including 142, 13 and 186 DEGs/DEPs commonly upregulated in the callus induction, maturation and development, respectively. Further, we found that the trihelix transcription factor ASR3 isoform X2 was commonly upregulated in the callus induction of the two eucalyptus species. The SOX30 and WRKY40 TFs were specifically upregulated in the callus induction of E. camaldulensis. Three TFs (bHLH62, bHLH35 isoform X2, RAP2-1) were specifically downregulated in the callus induction of E. grandis x urophylla. WGCNA identified 125 and 26 genes/proteins with high correlation (Pearson correlation > 0.8 or < -0.8) with ASR3 TF in the SE of E. camaldulensis and E. grandis x urophylla, respectively. The potential target gene expression patterns of ASR3 TF were then validated using qRT-PCR in the material. CONCLUSIONS: This is the first time to integrate multiple omics technologies to study the SE of eucalyptus. The findings will enhance our understanding of molecular regulation mechanisms of SE in eucalyptus. The output will also benefit the eucalyptus breeding program.


Assuntos
Eucalyptus , Técnicas de Embriogênese Somática de Plantas , Proteoma , Transcriptoma , Eucalyptus/genética , Eucalyptus/metabolismo , Eucalyptus/crescimento & desenvolvimento , Proteoma/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica
2.
Cell Commun Signal ; 22(1): 124, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360732

RESUMO

Autophagy is a self-renewal mechanism that maintains homeostasis and can promote tissue regeneration by regulating inflammation, reducing oxidative stress and promoting cell differentiation. The interaction between biomaterials and tissue cells significantly affects biomaterial-tissue integration and tissue regeneration. In recent years, it has been found that biomaterials can affect various processes related to tissue regeneration by regulating autophagy. The utilization of biomaterials in a controlled environment has become a prominent approach for enhancing the tissue regeneration capabilities. This involves the regulation of autophagy in diverse cell types implicated in tissue regeneration, encompassing the modulation of inflammatory responses, oxidative stress, cell differentiation, proliferation, migration, apoptosis, and extracellular matrix formation. In addition, biomaterials possess the potential to serve as carriers for drug delivery, enabling the regulation of autophagy by either activating or inhibiting its processes. This review summarizes the relationship between autophagy and tissue regeneration and discusses the role of biomaterial-based autophagy in tissue regeneration. In addition, recent advanced technologies used to design autophagy-modulating biomaterials are summarized, and rational design of biomaterials for providing controlled autophagy regulation via modification of the chemistry and surface of biomaterials and incorporation of cells and molecules is discussed. A better understanding of biomaterial-based autophagy and tissue regeneration, as well as the underlying molecular mechanisms, may lead to new possibilities for promoting tissue regeneration. Video Abstract.


Assuntos
Autofagia , Materiais Biocompatíveis , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Diferenciação Celular
3.
BMC Plant Biol ; 22(1): 558, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460945

RESUMO

BACKGROUND: Somatic embryogenesis (SE) was recognized as an important tool for plants to propagate. However, our knowledge about the proteins involved in early SE including the callus dedifferentiation is still limited, especially in the economic woody tree - Eucalyptus. RESULTS: We used the data-independent acquisition mass-spectrometry to study the different proteome profiles of early SE of two Eucalyptus species-E. camaldulensis (high regeneratively potential) and E. grandis x urophylla (low regenerative potential). Initially, 35,207 peptides and 7,077 proteins were identified in the stem and tissue-culture induced callus of the two Eucalyptus species. MSstat identified 2,078 and 2,807 differentially expressed proteins (DEPs) in early SE of E. camaldulensis and E. grandis x urophylla, respectively. They shared 760 upregulated and 420 downregulated proteins, including 4 transcription factors, 31 ribosomal proteins, 1 histone, 3 zinc finger proteins (ZFPs), 16 glutathione transferases, 10 glucosyltransferases, ARF19, WOX8 and PIN1. These proteins might be involved in the early SE of Eucalyptus. By combining the miRNA and RNA-Seq results, some miRNA ~ gene/protein regulatory networks were identified in early SE of Eucalyptus, such as miR160 ~ TPP2, miR164 ~ UXS2, miR169 ~ COX11 and miR535 ~ Eucgr.E01067. Further, we found SERK, WRKY, ZFP and ABC transporter might be related with high SE potential. CONCLUSIONS: Overall, our study identified proteins involved in the early SE and related to the high regeneration potential of Eucalyptus. It greatly enhanced our understanding of the early SE and the SE capacity of Eucalyptus.


Assuntos
Eucalyptus , MicroRNAs , Eucalyptus/genética , Proteoma/genética , Madeira , Desenvolvimento Embrionário
4.
BMC Plant Biol ; 22(1): 1, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979920

RESUMO

BACKGROUND: Eucalyptus is a highly diverse genus of the Myrtaceae family and widely planted in the world for timber and pulp production. Tissue culture induced callus has become a common tool for Eucalyptus breeding, however, our knowledge about the genes related to the callus maturation and shoot regeneration is still poor. RESULTS: We set up an experiment to monitor the callus induction and callus development of two Eucalyptus species - E. camaldulensis (high embryogenic potential) and E. grandis x urophylla (low embryogenic potential). Then, we performed transcriptome sequencing for primary callus, mature callus, shoot regeneration stage callus and senescence callus. We identified 707 upregulated and 694 downregulated genes during the maturation process of the two Eucalyptus species and most of them were involved in the signaling pathways like plant hormone and MAPK. Next, we identified 135 and 142 genes that might play important roles during the callus development of E. camaldulensis and E. grandis x urophylla, respectively. Further, we found 15 DEGs shared by these two Eucalyptus species during the callus development, including Eucgr.D00640 (stem-specific protein TSJT1), Eucgr.B00171 (BTB/POZ and TAZ domain-containing protein 1), Eucgr.C00948 (zinc finger CCCH domain-containing protein 20), Eucgr.K01667 (stomatal closure-related actinbinding protein 3), Eucgr.C00663 (glutaredoxin-C10) and Eucgr.C00419 (UPF0481 protein At3g47200). Interestingly, the expression patterns of these genes displayed "N" shape in the samples. Further, we found 51 genes that were dysregulated during the callus development of E. camaldulensis but without changes in E. grandis x urophylla, such as Eucgr.B02127 (GRF1-interacting factor 1), Eucgr.C00947 (transcription factor MYB36), Eucgr.B02752 (laccase-7), Eucgr.B03985 (transcription factor MYB108), Eucgr.D00536 (GDSL esterase/lipase At5g45920) and Eucgr.B02347 (scarecrow-like protein 34). These 51 genes might be associated with the high propagation ability of Eucalyptus and 22 might be induced after the dedifferentiation. Last, we performed WGCNA to identify the co-expressed genes during the callus development of Eucalyptus and qRT-PCR experiment to validate the gene expression patterns. CONCLUSIONS: This is the first time to globally study the gene profiles during the callus development of Eucalyptus. The results will improve our understanding of gene regulation and molecular mechanisms in the callus maturation and shoot regeneration.


Assuntos
Eucalyptus/genética , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais
5.
Dermatol Ther ; 35(12): e15910, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36208443

RESUMO

Ustekinumab (brand name Stelara®) is a human interleukin-12 and -23 antagonist and has been indicated for the treatments of moderate to severe plaque psoriasis, psoriatic arthritis, Crohn's disease and ulcerative colitis. This review aims to synthesize and interpret the literature evaluating the off-label uses of ustekinumab. We performed searches in PubMed and ClinicalTrials.gov for clinical trials, observational studies, case series, and case reports evaluating label uses of ustekinumab. Studies evaluated the efficacy of ustekinumab for the following conditions: other types of psoriasis (expect plaque psoriasis and psoriatic arthritis), pityriasis rubra pilaris, hidradenitis suppurativa, atopic dermatitis, pyoderma gangrenosum, et al. Based on the available literature, ustekinumab appears to be a potential treatment choice for many other diseases. However, more clinical trials data are needed to adequately assess the safety and efficacy of ustekinumab for the treatment of these conditions.


Assuntos
Artrite Psoriásica , Pitiríase Rubra Pilar , Psoríase , Humanos , Ustekinumab/efeitos adversos , Artrite Psoriásica/tratamento farmacológico , Uso Off-Label , Psoríase/tratamento farmacológico , Pitiríase Rubra Pilar/tratamento farmacológico
6.
Pharmacol Res ; 165: 105435, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33485996

RESUMO

Our previous studies found that prenatal dexamethasone exposure could cause abnormal follicular development in fetal rats. This study intends to observe the transgenerational inheritance effects of ovarian estrogen inhibition in offspring exposed to dexamethasone (0.2 mg/kg • d) from gestational day 9 (GD9) to GD20 in Wistar rats, and explore the intrauterine programming mechanisms. Prenatal dexamethasone exposure reduced the expression of ovarian cytochrome P450 aromatase (P450arom), the level of serum estradiol (E2) and the number of primordial follicles, while increased the number of atresia follicles before and after birth in F1 offspring rats. At the same time, the expression of miRNA320a-3p in F1 ovaries was down-regulated, and RUNX2 expression increased significantly. These changes were continued to F2 and F3 generations, accompanied by consistently down-regulated miRNA320a-3p expression in oocyte of F1 and F2 adult offspring. In vitro, fetal rat ovaries and KGN human ovarian granulosa cells were treated with dexamethasone. It showed that dexamethasone decreased miRNA320a-3p and P450arom expression, as well as E2 synthesis, and increased RUNX2 expression. All these effects could be reversed by the GR antagonist RU486. The overexpression of miRNA320a-3p in vitro could also reverse the effects of dexamethasone on RUNX2, P450arom, and E2 levels. The dual-luciferase reporter gene experiment further confirmed the direct targeted regulation of miRNA320a-3p on RUNX2. These results indicate that prenatal dexamethasone exposure induces ovarian E2 synthesis inhibition mediated by the GR/miRNA320a-3p/RUNX2/P450arom cascade signal in fetal rat ovary, which has transgenerational inheritance effects and may related to the inhibited miRNA320a-3p expression in oocyte.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core/biossíntese , Dexametasona/toxicidade , Estrogênios/biossíntese , MicroRNAs/sangue , Ovário/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Animais Recém-Nascidos , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Glucocorticoides/toxicidade , Humanos , MicroRNAs/antagonistas & inibidores , Ovário/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Ratos Wistar , Inibidores da Síntese de Esteroides/toxicidade
7.
Zhonghua Wai Ke Za Zhi ; 53(5): 392-5, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26082256

RESUMO

Laparoscopic spleen-preserving splenic hilar lymphadenectomy (LSPL) is a operation conducted experimentally in the current. Current reports showed that it can be safely completed through different approach, such as the right, left, medial and retropancreatic approach. This paper summarized the steps and characteristics of different approaches LSPL and compared the differences between each other. The application status of LSPL in laparoscopy-assisted radical gastrectomy were reviewed. The security, feasibility and the problem to be solved of LSPL, improvement measure also be explored in this paper.


Assuntos
Gastrectomia/métodos , Excisão de Linfonodo/métodos , Neoplasias Gástricas/cirurgia , Humanos , Laparoscopia , Linfonodos , Baço
8.
Heart Vessels ; 29(4): 486-95, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23836068

RESUMO

Despite a recent epidemiological study reporting a lower incidence of sudden cardiac death (SCD) in China as compared with that in Western countries, the exact causes of SCD are still unknown. Using a uniform review protocol and diagnostic criteria, a retrospective autopsy study identified 553 cases of SCD in 14,487 consecutive autopsies from eight regions in China representing different geographic and population features. Their ages ranged from 18 to 80 years (median 43.0 years) with a ratio of 4.3/1.0 for male/female. Out-of-hospital deaths and unwitnessed cases accounted for 74.3 and 22.6 %, respectively. The main causes of death were coronary atherosclerotic disease (CAD 50.3 %), myocarditis (14.8 %), and hypertrophic cardiomyopathy (4.5 %), with unexplained sudden death accounting for 12.1 % of the cases. CAD had a proportion of 10.4 % in victims <35 years, lower as compared with 59.0 and 83.0 % in victims aged 35-54 and in victims ≥55 years. On the other hand, myocarditis and unexplained sudden death were major causes and accounted for 34.7 and 22.5 % in victims <35 years. In order to differentiate the degree of the cause-effect relationship between autopsy findings and sudden death, a grading method was used in this series and characterized 24.3 % of findings as certain, 52.9 % as highly probable, and 22.8 % as uncertain. Our data indicated that there most likely are less CAD but more myocarditis and unexplained sudden death in Chinese youth with SCD than in populations from Western countries. Molecular genetic testing should be conducted in those cases with uncertain findings and unexplained sudden death in routine autopsy.


Assuntos
Povo Asiático , Morte Súbita Cardíaca/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Autopsia , Causas de Morte , China/epidemiologia , Vasos Coronários/patologia , Morte Súbita Cardíaca/etnologia , Sistema de Condução Cardíaco/patologia , Valvas Cardíacas/patologia , Mortalidade Hospitalar , Humanos , Pessoa de Meia-Idade , Miocárdio/patologia , Estudos Retrospectivos , Adulto Jovem
9.
Materials (Basel) ; 17(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612058

RESUMO

Seismic anti-seismic rebar, as materials for supporting structures in large buildings, need to have excellent mechanical properties. By increasing the Nb content and controlling the cooling rate, the microstructure and precipitation behavior of the steel are adjusted to develop seismic anti-seismic rebar with excellent mechanical properties. Scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and a universal tensile testing machine were used to characterize the microstructure, precipitation phases, and mechanical properties of the experimental steels. The results show that the ferrite grain size, pearlite lamellae layer (ILS), and small-angle grain boundaries (LAGB) content of the high-Nb steels decreased to 6.39 µm, 0.12 µm, and 48.7%, respectively, as the Nb content was increased from 0.017 to 0.023 wt.% and the cooling rate was increased from 1 to 3 °C·s-1. The strength of the {332}<113>α texture is the highest in the high-Nb steels. The precipitated phase is (Nb, Ti, V)C with a diameter of ~50 nm, distributed on ferrite, and the matrix/precipitated phase mismatch is 8.16%, forming a semicommon-lattice interface between the two. The carbon diffusion coefficient model shows that increasing the Nb content can inhibit the diffusion of carbon atoms and reduce the ILS. The yield strength of the high-Nb steel is 556 MPa, and the tensile strength is 764 MPa.

10.
Materials (Basel) ; 17(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38541546

RESUMO

High-carbon hardline steels are primarily used for the manufacture of tire beads for both automobiles and aircraft, and vanadium (V) microalloying is an important means of adjusting the microstructure of high-carbon hardline steels. Using scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM), the microstructure and precipitation phases of continuous cooled high-carbon steels were characterized, and the vanadium content, carbon diffusion coefficient, and critical precipitation temperature were calculated. The results showed that as the V content increased to 0.06 wt.%, the interlamellar spacing (ILS) of the pearlite in the experimental steel decreased to 0.110 µm, and the carbon diffusion coefficient in the experimental steel decreased to 0.98 × 10-3 cm2·s-1. The pearlite content in the experimental steel with 0.02 wt.% V reached its maximum at a cooling rate of 5 °C·s-1, and a small amount of bainite was observed in the experimental steel at a cooling rate of 10 °C·s-1. The precipitated phase was VC with a diameter of ~24.73 nm, and the misfit between ferrite and VC was 5.02%, forming a semi-coherent interface between the two. Atoms gradually adjust their positions to allow the growth of VC along the ferrite direction. As the V content increased to 0.06 wt.%, the precipitation-temperature-time curve (PTT) shifted to the left, and the critical nucleation temperature for homogeneous nucleation, grain boundary nucleation, and dislocation line nucleation increased from 570.6, 676.9, and 692.4 °C to 634.6, 748.5, and 755.5 °C, respectively.

11.
Materials (Basel) ; 16(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37512343

RESUMO

In this paper, an experimental protocol of adding rare earth lanthanum (La) was used to refine and modify inclusions (Al2O3) in aluminum-deoxidized steel. An optical microscope (OM), a scanning electron microscope (SEM), and an energy dispersive spectrometer (EDS) were used to study the impact of size distribution, number density, distribution uniformity, interfacial distance, area density, and so on of rare earth La on high-carbon hard wire steel inclusions. As indicated by the findings when the addition amount of La is 0.063%, the refining and homogenizing effect of Al2O3 inclusions in steel is the best. The average diameter of the inclusions is 1.75 µm, the uniformity is 0.84, the proportion of the interfacial spacing greater than 10 µm is 48.4%, and the area density of inclusions is set at 0.014. Based on classical thermodynamics and Factsage software, the effect of La activity on inclusion formation was computed. As indicated by the findings, the addition of rare earth La mainly combines with O and S in the liquid steel, and the La-containing inclusions wrap around the Al2O3 inclusions, hindering the Al2O3 inclusions. Through the evolution of inclusions during solidification, the modification of Al2O3 inclusions via rare earth La and the types of inclusions are discussed. The experimental results and theoretical calculations verify that the optimal treatment plan is to add 0.063% La.

12.
J Hazard Mater ; 445: 130621, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-37056005

RESUMO

The disposal and large-scale reutilization of industrial solid waste in construction materials have been gaining considerable interest. Herein, the synthesis of glass-ceramics from low-carbon ferrochromium slag (FCS) and waste glass is reported. The crystallization characteristics, microstructural evolution, and Cr migration mechanisms of the glass-ceramics were investigated through offline quenching experiments. The physical properties and Cr ion leaching performance were tested and evaluated. As the low-carbon FCS content was increased, glass network depolymerization was promoted and the crystallization ability was effectively improved. When 50 wt% low-carbon FCS was added, the compressive strength and Vickers hardness of the glass-ceramics reached maximum values of 160.26 MPa and 736 Hv, respectively. Simultaneously, the dominant crystalline phase in glass-ceramics was transformed from diopside and wollastonite into gehlenite when the low-carbon FCS content was further increased to 60 wt%, thereby reducing the mechanical properties. Cr2O3 primarily existed as a [CrO6] octahedron and Cr-containing spinel in the parent glass, resulting in composition segregation. On combining the growth orientation of diopside and spinel, the resulting specific crystal coating structure improved the Cr ion leaching performance. Considering the physical properties and risk of Cr leaching, the optimal FCS content in glass-ceramics is 40-50 wt%. These findings indicate that the production of glass-ceramics from low-carbon FCS and waste glass is an effective and environment-friendly method for co-utilizing these two solid wastes.

13.
Medicine (Baltimore) ; 102(42): e34512, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37861497

RESUMO

Tripterygium wilfordii hook (TWH) has been used to treat Behcet's disease (BD) but its underlying mechanism remains unclear. This study aims to explore the mechanism of TWH on BD using network pharmacology and molecular docking. The bioactive constituents of TWH and their corresponding target genes were extracted from the Traditional Chinese Medicine systems pharmacology database and analysis platform. BD target genes were obtained by searching the DisGeNet and GeneCards databases. Gene ontology annotation and Kyoto encyclopedia of genes and genomes pathway enrichment analysis were conducted to elucidate the function of overlapping genes between TWH and BD target genes. A protein-protein interaction network was constructed using Cytoscape and STRING platforms, and the core target genes were identified from the overlapping genes. Finally, molecular docking was used to assess the binding affinity between the core targets and TWH bioactive constituents. We identified 25 intersection genes related to both TWH and BD and 27 bioactive ingredients of TWH. Through analysis of protein-protein interaction network, 6 core targets (TNF, IFNG, prostaglandin-endoperoxide synthase 2, NOS2, VCAM-1, and interleukin-2) were screened out. Enrichment analysis demonstrated that the antioxidant properties of TWH constituents might play a significant role in their therapeutic effects. Molecular docking revealed high binding affinity between the bioactive constituents of TWH, such as kaempferol, triptolide, 5, 8-Dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3)-coumarin, and their corresponding target genes, suggesting the potential of TWH to treat BD. Our investigation clarified the active components, therapeutic targets of BD in the treatment of TWH and provided a theoretical foundation for further researches.


Assuntos
Síndrome de Behçet , Medicamentos de Ervas Chinesas , Humanos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Tripterygium , Síndrome de Behçet/tratamento farmacológico , Cumarínicos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa
14.
Orphanet J Rare Dis ; 18(1): 234, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559063

RESUMO

Osteogenesis imperfecta (OI) is a connective tissue disorder affecting the skeleton and other organs, which has multiple genetic patterns, numerous causative genes, and complex pathogenic mechanisms. The previous classifications lack structure and scientific basis and have poor applicability. In this paper, we summarize and sort out the pathogenic mechanisms of OI, and analyze the molecular pathogenic mechanisms of OI from the perspectives of type I collagen defects(synthesis defects, processing defects, post-translational modification defects, folding and cross-linking defects), bone mineralization disorders, osteoblast differentiation and functional defects respectively, and also generalize several new untyped OI-causing genes and their pathogenic mechanisms, intending to provide the evidence of classification and a scientific basis for the precise diagnosis and treatment of OI.


Assuntos
Doenças Ósseas , Osteogênese Imperfeita , Humanos , Osteogênese Imperfeita/genética , Colágeno Tipo I/genética , Osteogênese/genética , Calcificação Fisiológica , Mutação
15.
Materials (Basel) ; 16(8)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37109949

RESUMO

Scrap steel is a kind of resource that can be recycled indefinitely. However, the enrichment of arsenic in the recycling process will seriously affect the performance of the product, making the recycling process unsustainable. In this study, the removal of arsenic from molten steel using calcium alloys was investigated experimentally, and the underlying mechanism was explored based on thermodynamic principles. The results show that the addition of calcium alloy is an effective means of reducing the arsenic content in molten steel, with the highest removal percentage of 56.36% observed with calcium aluminum alloy. A thermodynamic analysis revealed that the critical calcium content required for arsenic removal reaction is 0.0037%. Moreover, ultra-low levels of oxygen and sulfur were found to be crucial in achieving a good arsenic removal effect. When the arsenic removal reaction occurs in molten steel, the oxygen and sulfur concentrations in equilibrium with calcium were wO=0.0012% and wS=0.00548%, respectively. After successful arsenic removal, the arsenic removal product of the calcium alloy is Ca3As2, which usually does not appear alone. Instead, it is prone to combining with alumina, calcium oxide, and other inclusions to form composite inclusions, which is beneficial for the floating removal of inclusions and the purification of scrap steel in molten steel.

16.
ACS Omega ; 7(37): 33560-33571, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36157730

RESUMO

Substantial heterogeneity in lacustrine shale brings significant challenges to oil exploration. Therefore, a clear and effective resource evaluation standard can significantly reduce the exploration risk and cost, thus further guiding the prediction in productive areas. However, due to the lack of consideration of the thermal maturity and kerogen type, the present evaluation standards may result in the misjudgment of the resource quality of shale oil reservoirs. In this study, a method based on mass balance involving a hydrocarbon generation statistical model was proposed to calculate oil movable threshold (OMT) values. The OMT values for different types of kerogens are determined from simple and easily obtained pyrolysis parameters. Based on the OMT values, a three-dimensional resource quality evaluation model is constructed and applied to the source rocks in Member (Mbr) 1 of the Shahejie Formation (Fm) Nanpu Sag, Bohai Bay Basin, eastern China. The results show that the Mbr 1 of Shahejie Fm shale is a set of high-quality source rocks with high total organic matter (TOC) and S1c (calibrated free hydrocarbons) content. Meanwhile, the hydrocarbon generation potential of the studied lacustrine shales are in the order of type I > type II1 > type II2 > type III, whereas the OMT values show a similar order. From type I to type III, the hydrocarbon expulsion threshold (HET) values for the four types of shales correspond to pyrolysis peak temperatures (T max) at 438, 426, 428, and 432 °C with the maximum OMT values being 143, 128, 127, and 122 mg HC/g TOC, respectively. The movable and favorable shale oil accumulations are mainly associated with type II1 and II2 shales. Our work provides a novel method for distinguishing the resource quality and locating a favorable exploration target for lacustrine shale, improving efficiency and reducing exploration risks.

17.
Materials (Basel) ; 15(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35629463

RESUMO

Thermal deformation has a significant influence on the microstructure of high-strength antiseismic steel. The effect of hot deformation on the microstructure of experimental steel was studied by the Gleeble-3800 thermal simulator. The microstructure of the steel was characterized by the metallographic microscope, microhardness, tensile test, field emission scanning electron microscope, electron backscatter diffraction, and high-resolution transmission electron microscope. The results show that the core microstructure of the test steel is composed of polygonal ferrite and lamellar pearlite. The test steel is mainly ductile fracture. Tensile strength and hardness increase with the decrease of temperature. At 650 °C isothermal temperature, the ferrite distribution was uniform, the average grain size was 7.78 µm, the grain size grade reached 11, the pearlite lamellar spacing was 0.208 µm, and the tensile fracture was distributed with uniform equiaxed dimples. Polygonal ferrite grain boundaries have high density dislocations that can effectively block the initiation and propagation of cracks. However, there are some low dislocation boundaries and subgrain boundaries in ferrite grains. Precipitation strengthening is mainly provided by fine precipitates of V-rich carbonitride in experimental steel. The precipitates are round or narrow strips, about 70-100 nm in size, distributed along ferrite grain boundaries and matrix.

18.
Bioengineered ; 13(5): 11732-11741, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35506298

RESUMO

Acute respiratory distress syndrome (ARDS) is a multifactorial inflammatory lung failure with a high incidence and a high cost burden. However, the underlying pathogenesis of ARDS is still unclear. Recently, microRNA has been shown to have critical function in regulating the pathogenesis of ARDS development and inflammation. To identify the important microRNA in the serum from patients with ARDS that may be potential biomarkers for the disease and explore the underlying disease mechanism. We found significant upregulation of miR-155-5p expression in serum samples from patients with ARDS compared with the control group (p < 0.01). The levels of interleukin receptors and inflammatory cytokines were significantly increased in blood samples from patients with ARDS (p < 0.05). In the cell model, miR-155-5p had a binding site in the 3'-UTR of the three interleukin receptors. In LPS-simulated BEAS-2B cells, transfection of miR-155-5p mimic inhibited the expression levels of these interleukin receptors, and was found to directly target the inflammatory response of leukocyte nodulin receptor through NF-kB signaling. In conclusion, miR-155-5p can alleviate LPS-simulated injury that induces the expression of IL17RB, IL18R1, and IL22RA2 by affecting the NF-kB pathway; however, it cannot change the occurrence of inflammatory storms. Collectively, this suggests that the progression of ARDS is the result of effects of the multiple regulatory pathways, providing novel evidence for the therapy of ARDS.


Assuntos
MicroRNAs , Síndrome do Desconforto Respiratório , Humanos , Lipopolissacarídeos , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Receptores de Interleucina/genética , Síndrome do Desconforto Respiratório/genética
19.
Materials (Basel) ; 15(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36556745

RESUMO

The effects of niobium and composite strengthening on the phase transformation characteristics and precipitation behavior of continuous cooling transformation of high-strength rebar during thermal deformation and subsequent cooling were investigated. The results show that when the cooling rate was within 0.3-5 °C/s, ferrite transformation and pearlite transformation occurred in the experimental steels. The Nb content increased to 0.062 wt.%, and the starting temperature of the ferrite transformation decreased. Meanwhile, the ferrite phase transformation zone gradually expanded, and the pearlite phase transformation zone gradually narrowed with the increase in the cooling rate. When the cooling rate was 1 °C/s, bainite transformation began to occur, and the amount of transformation increased with the increase in the cooling rate. It was found that the main precipitates in the experimental steels were (Nb, Ti, V)C, with an average particle size of about 10-50 nm. When the Nb content was increased to 0.062 wt.% and the cooling rate was increased to 5 °C/s, the ferrite grain size was reduced from 19.5 to 7.5 µm, and the particle size of the precipitate (Nb, Ti, V)C could be effectively reduced. The strength of the steel was significantly improved, but the elongation of the steel was reduced. However, the comprehensive mechanical properties of 0.062 wt.% Nb experimental steel was significantly improved at a cooling rate of 5 °C/s.

20.
Front Physiol ; 13: 948965, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277211

RESUMO

The centrosome regulates mammalian meiosis by affecting recombination, synapsis, chromosome segregation, and spermiogenesis. Cep72 is one of the critical components of the centrosome. However, the physiological role of Cep72 in spermatogenesis and fertility remains unclear. In this study, we identify Cep72 as a testis-specific expression protein. Although Cep72 knockout mice were viable and fertile, their sperms were morphologically abnormal with incomplete flagellum structures. Transcriptome analysis reveals significant differences in six genes (Gm49527, Hbb-bt, Hba-a2, Rps27a-ps2, Gm29647, and Gm8430), which were not previously associated with spermatogenesis. Overall, these results indicate that Cep72 participates in regulating sperm morphology and yet is dispensable for fertility in mice.

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