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1.
J Cell Mol Med ; 27(21): 3313-3325, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37593898

RESUMO

Mitochondria are sensitive organelles that sense intrinsic and extrinsic stressors and maintain cellular physiological functions through the dynamic homeostasis of mitochondrial fusion and fission. Numerous pathological processes are associated with mitochondrial fusion and fission disorders. However, the molecular mechanism by which stress induces cardiac pathophysiological changes through destabilising mitochondrial fusion and fission is unclear. Therefore, this study aimed to investigate whether the endoplasmic reticulum stress signalling pathway initiated by the turbulence of mitochondrial fusion and fission under stressful circumstances is involved in cardiomyocyte damage. Based on the successful establishment of the classical stress rat model of restraint plus ice water swimming, we measured the content of serum lactate dehydrogenase. We used haematoxylin-eosin staining, special histochemical staining, RT-qPCR and western blotting to clarify the cardiac pathology, ultrastructural changes and expression patterns of mitochondrial fusion and fission marker proteins and endoplasmic reticulum stress signalling pathway proteins. The results indicated that mitochondrial fusion and fission markers and proteins of the endoplasmic reticulum stress JNK signalling pathway showed significant abnormal dynamic changes with the prolongation of stress, and stabilisation of mitochondrial fusion and fission using Mdivi-1 could effectively improve these abnormal expressions and ameliorate cardiomyocyte injury. These findings suggest that stress could contribute to pathological cardiac injury, closely linked to the endoplasmic reticulum stress JNK signalling pathway induced by mitochondrial fusion and fission turbulence.


Assuntos
Dinâmica Mitocondrial , Miócitos Cardíacos , Ratos , Animais , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Estresse do Retículo Endoplasmático/genética
2.
J Am Chem Soc ; 145(28): 15507-15527, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37392467

RESUMO

We combine experimental and computational investigations to compare and understand catalytic arene alkenylation using the Pd(II) and Rh(I) precursors Pd(OAc)2 and [(η2-C2H4)2Rh(µ-OAc)]2 with arene, olefin, and Cu(II) carboxylate at elevated temperatures (>120 °C). Under specific conditions, previous computational and experimental efforts have identified heterotrimetallic cyclic PdCu2(η2-C2H4)3(µ-OPiv)6 and [(η2-C2H4)2Rh(µ-OPiv)2]2(µ-Cu) (OPiv = pivalate) species as likely active catalysts for these processes. Further studies of catalyst speciation suggest a complicated equilibrium between Cu(II)-containing complexes containing one Rh or Pd atom with complexes containing two Rh or Pd atoms. At 120 °C, Rh catalysis produces styrene >20-fold more rapidly than Pd. Also, at 120 °C, Rh is ∼98% selective for styrene formation, while Pd is ∼82% selective. Our studies indicate that Pd catalysis has a higher predilection toward olefin functionalization to form undesired vinyl ester, while Rh catalysis is more selective for arene/olefin coupling. However, at elevated temperatures, Pd converts vinyl ester and arene to vinyl arene, which is proposed to occur through low-valent Pd(0) clusters that are formed in situ. Regardless of arene functionality, the regioselectivity for alkenylation of mono-substituted arenes with the Rh catalyst gives an approximate 2:1 meta/para ratio with minimal ortho C-H activation. In contrast, Pd selectivity is significantly influenced by arene electronics, with electron-rich arenes giving an approximate 1:2:2 ortho/meta/para ratio, while the electron-deficient (α,α,α)-trifluorotoluene gives a 3:1 meta/para ratio with minimal ortho functionalization. Kinetic intermolecular arene ethenylation competition experiments find that Rh reacts most rapidly with benzene, and the rate of mono-substituted arene alkenylation does not correlate with arene electronics. In contrast, with Pd catalysis, electron-rich arenes react more rapidly than benzene, while electron-deficient arenes react less rapidly than benzene. These experimental findings, in combination with computational results, are consistent with the arene C-H activation step for Pd catalysis involving significant η1-arenium character due to Pd-mediated electrophilic aromatic substitution character. In contrast, the mechanism for Rh catalysis is not sensitive to arene-substituent electronics, which we propose indicates less electrophilic aromatic substitution character for the Rh-mediated arene C-H activation.

3.
Arch Insect Biochem Physiol ; 111(2): e21910, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35470488

RESUMO

The nuclear receptor (NRs) gene family functions as ligand-dependent transcription factors in a variety of animals, which participates in a variety of biological processes, such as cell differentiation, metabolic regulation, reproduction, development, insect metamorphosis. In this study, a nuclear receptor HR96 gene in silkworm Bombyx mori (BmHR96) was identified, and the responses of BmHR96 gene to 20-hydroxyecdysone (20E), three insecticides, and two disinfectants were analyzed and its function in phoxim exposure was explored.  Quantitative real-time polymerase chain reaction indicated that the expression of BmHR96 mRNA was the highest in ovary of 5th instar Day 3 silkworm larvae and in silk gland of the wandering stage. The expression patterns of BmHR96 gene in ovary, head, testis, and midgut of different stages were different. After injecting 20E into B. mori, the expression of BmHR96 mRNA had no significant difference compared with control. Three insecticides and two disinfectants were used to treat B. mori, respectively, and it was found that they had different influence patterns on the expression level of BmHR96. siRNA of BmHR96 was injected into silkworm larvae and the expression of BmHR96 was decreased significantly after injecting 72 h. After silencing of BmHR96, B. mori was fed with phoxim-treated leaves. The results showed that the mortality of B. mori after silencing of BmHR96 was significantly higher than the control. Our results indicated that HR96 plays an important role in regulating the stress response of phoxim.


Assuntos
Bombyx , Desinfetantes , Inseticidas , Animais , Bombyx/metabolismo , Desinfetantes/farmacologia , Proteínas de Insetos/metabolismo , Inseticidas/farmacologia , Larva/metabolismo , Compostos Organotiofosforados , RNA Mensageiro
4.
Zhongguo Zhong Yao Za Zhi ; 47(17): 4560-4564, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164860

RESUMO

Animal medicine is a large category of Chinese medicinecommonly used in clinical practice and has important scientific and therapeutic value. Animal medicine isscarcer than herbal medicine. In recent years, with the vigorous development of traditional Chinese medicine(TCM),the contradiction between the increasing industrial demand andsupply of scarce and even endangered medicinal animals has become increasingly prominent. The continuous lack of medicinal animal resources affects the clinical demandandalso causes serious damage to the ecological environment. Only relying on artificial breeding is not enough to alleviate the current condition of depletion. In the face of this dilemma, it is a major challenge for the current industrial development to protect animal resources and meet clinical and industrial needs with "available medicines". The application of substitutes for animal medicines isthe key focus to alleviate this problem, and it is also the key scientific issue to be solved urgently in the modernization of TCM. This paper summarizedand reviewedthe history, current situation, strategies, and methods of animal medicinesubstitution and put forward the point of view of "similar chemical characteristics, similar efficacy, and higher safety" to provide references for scientific substitution and resource protection of rare animals.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Animais , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Melhoramento Vegetal , Projetos de Pesquisa
5.
J Am Chem Soc ; 143(18): 6746-6766, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33908253

RESUMO

On a large scale, the dominant method to produce alkyl arenes has been arene alkylation from arenes and olefins using acid-based catalysis. The addition of arene C-H bonds across olefin C═C bonds catalyzed by transition-metal complexes through C-H activation and olefin insertion into metal-aryl bonds provides an alternative approach with potential advantages. This Perspective presents recent developments of olefin hydroarylation and oxidative olefin hydroarylation catalyzed by molecular complexes based on group 10 transition metals (Ni, Pd, Pt). Emphasis is placed on comparisons between Pt catalysts and other group 10 metal catalysts as well as Ru, Ir, and Rh catalysts.

6.
Acc Chem Res ; 53(4): 920-936, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32239913

RESUMO

ConspectusAlkyl and alkenyl arenes are of substantial value in both large-scale and fine chemical processes. Billions of pounds of alkyl and alkenyl arenes are produced annually. Historically, the dominant method for synthesis of alkyl arenes is acid-catalyzed arene alkylation, and alkenyl arenes are often synthesized in a subsequent dehydrogenation step. But these methods have limitations that result from the catalytic mechanism including (1) common polyalkylation, which requires an energy intensive transalkylation process, (2) quantitative selectivity for Markovnikov products for arene alkylation using α-olefins, (3) for substituted arenes, regioselectivity that is dictated by the electronic character of the arene substituents, (4) inability to form alkenyl arenes in a single process, and (5) commonly observed slow reactivity with electron-deficient arenes. Transition-metal-catalyzed aryl-carbon coupling reactions can produce alkyl or alkenyl arenes from aryl halides. However, these reactions often generate halogenated waste and typically require a stoichiometric amount of metal-containing transmetalation reagent. Transition-metal-catalyzed arene alkylation or alkenylation that involves arene C-H activation and olefin insertion into metal-aryl bonds provides a potential alternative method to prepare alkyl or alkenylation arenes. Such reactions can circumvent carbocationic intermediates and, as a result, can overcome some of the limitations mentioned above. In particular, controlling the regioselectivity of the insertion of α-olefins into metal-aryl bonds provides a strategy to selectively synthesize anti-Markovnikov products. But, previously reported catalysts often show limited longevity and low selectivity for anti-Markovnikov products.In this Account, we present recent developments in single-step arene alkenylation using Rh catalyst precursors. The reactions are successful for unactivated hydrocarbons and exhibit unique selectivity. The catalytic production of alkenyl arenes operates via Rh-mediated aromatic C-H activation, which likely occurs by a concerted metalation-deprotonation mechanism, olefin insertion into a Rh-aryl bond, ß-hydride elimination from the resulting Rh-hydrocarbon product, and net dissociation of alkenyl arene with formation of a Rh hydride. Reaction of the Rh hydride with Cu(II) oxidant completes the catalytic cycle. Although Rh nanoparticles can be formed under some conditions, mechanistic studies have revealed that soluble Rh species are likely responsible for the catalysis. These Rh catalyst precursors achieve high turnovers with >10,000 catalytic turnovers observed in some cases. Under anaerobic conditions, Cu(II) carboxylates are used as the oxidant. In some cases, aerobic recycling of Cu(II) oxidant has been demonstrated. Hence, the Rh arene alkenylation catalysis bears some similarities to Pd-catalyzed olefin oxidation (i.e., the Wacker-Hoechst process). The Rh-catalyzed arene alkenylation is compatible with some electron-deficient arenes, and they are selective for anti-Markovnikov products when using substituted olefins. Finally, when using monosubstituted arenes, consistent with a metal-mediated C-H activation process, Rh-catalyzed alkenylation of substituted arenes shows selectivity for meta- and para-alkenylation products.

7.
Oral Dis ; 27(7): 1747-1754, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33128317

RESUMO

OBJECTIVE: To explore susceptibility genes and pathways for non-syndromic cleft lip with or without cleft palate (NSCL/P). MATERIALS AND METHODS: Two genome-wide association studies (GWAS) datasets, including 858 NSCL/P cases and 1,248 controls, were integrated with expression quantitative trait loci (eQTL) dataset identified by Genotype-Tissue Expression (GTEx) project in whole-blood samples. The expression of the candidate genes in mouse orofacial development was inquired from FaceBase. Protein-protein interaction (PPI) network was visualized to identify protein functions. Go and KEGG pathway analyses were performed to explore the underlying risk pathways. RESULTS: A total of 233 eQTL single-nucleotide polymorphisms (SNPs) in 432 candidate genes were identified to be associated with the risk of NSCL/P. One hundred and eighty-three susceptible genes were expressed in mouse orofacial development according to FaceBase. PPI network analysis highlighted that these genes involved in ubiquitin-mediated proteolysis (KCTD7, ASB1, UBOX5, ANAPC4) and DNA synthesis (XRCC3, RFC3, KAT5, RHNO1) were associated with the risk of NSCL/P. GO and KEGG pathway analyses revealed that the fatty acid metabolism pathway (ACADL, HSD17B12, ACSL5, PPT1, MCAT) played an important role in the development of NSCL/P. CONCLUSIONS: Our results identified novel susceptibility genes and pathways associated with the development of NSCL/P.


Assuntos
Fenda Labial , Fissura Palatina , 17-Hidroxiesteroide Desidrogenases , Animais , Estudos de Casos e Controles , Fenda Labial/genética , Fissura Palatina/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Camundongos , Polimorfismo de Nucleotídeo Único , Canais de Potássio , Locos de Características Quantitativas/genética , Proteínas Supressoras da Sinalização de Citocina
8.
J Obstet Gynaecol Res ; 47(12): 4440-4449, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34643014

RESUMO

AIMS: This study aimed to create a structural equation model to evaluate the associations among demographic factors, health education, breast cancer-related knowledge, attitudes, and breast self-examination behavior among Chinese female college students. METHODS: A survey was undertaken using a self-administered questionnaire and targeting 2233 students from Eastern China. Structural equation modeling with the bootstrap approach was utilized to estimate the interrelationships and the strength of the associations among measured variables based on the hypothetical model. RESULTS: Among the total participants, 14.7% of the female college students reported having performed breast self-examination. The final structural equation model showed highly satisfactory fitness on indices. Breast self-examination behavior was significantly linked to demographic factors, breast cancer related-knowledge, attitudes, and health education. Health education had the greatest influence on breast self-examination behavior. In addition, breast cancer related-knowledge was significantly associated with demographic factors and health education. Health education and knowledge all significantly affected attitudes towards breast cancer. CONCLUSION: Breast self-examination behavior was influenced by demographic factors, breast cancer related-knowledge, attitudes towards breast cancer, and health education in a sample of female college students in China. Health education was the most important predictor of breast self-examination behavior.


Assuntos
Neoplasias da Mama , Autoexame de Mama , China , Demografia , Feminino , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudantes , Inquéritos e Questionários , Universidades
9.
J Am Chem Soc ; 142(23): 10534-10543, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32453558

RESUMO

Arene alkenylation is commonly achieved by late transition metal-mediated C(sp2)-C(sp2) cross-coupling, but this strategy typically requires prefunctionalized substrates (e.g., with halides or pseudohalides) and/or the presence of a directing group on the arene. Transition metal-mediated arene C-H activation and alkenylation offers an alternative method to functionalize arene substrates. Herein, we report a rhodium-catalyzed oxidative arene alkenylation from arenes and styrenes to prepare stilbene and stilbene derivatives. The reaction is successful with several functional groups on both the arene and the olefin including fluoride, chloride, trifluoromethyl, ester, nitro, acetate, cyanide, and ether groups. Reactions of monosubstituted arenes are selective for alkenylation at the meta and para positions, generally with approximately 2:1 selectivity, respectively. Resveratrol and (E)-1,2,3-trimethoxy-5-(4-methoxystyryl)benzene (DMU-212) are synthesized by this single-step approach in high yield. Comparison with palladium catalysis showed that rhodium catalysis is more selective for meta-functionalization for monosubstituted arenes and that the Rh catalysis has better tolerance of halogen groups.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 43(1): 100-105, 2018 Jan 28.
Artigo em Zh | MEDLINE | ID: mdl-30154299

RESUMO

Two patients with primary hypertrophic osteoarthropathy (PHO) and their available healthy family members were studied. All exons of the SLCO2A1 and HPGD gene and adjacent exon-intron sequences were amplified by PCR and subsequently sequenced. To assess the damaging effects of missense mutations in silico, the online database, PolyPhen-2 and SIFT were used. We identified two homozygous mutations in SLCO2A1 gene: one was c.1106G>A (p.G369D) in exon 9, the other was c.611C>T (p.S204L) in exon 4. No HPGD mutation was found in the affected individuals. The two mutation were predicted in silico by the bioinformatic tools. Our study further supports the role of mutations in the SLCO2A1 gene in the pathogenesis of PHO. Identification of the genotype in PHO may not only help the clinical diagnosis of PHO but also help the interpretation of genetic information for prenatal diagnosis and genetic counseling.


Assuntos
Mutação de Sentido Incorreto , Transportadores de Ânions Orgânicos/genética , Osteoartropatia Hipertrófica Primária/genética , Análise Mutacional de DNA , Éxons/genética , Feminino , Genótipo , Humanos , Hidroxiprostaglandina Desidrogenases/genética , Linhagem , Gravidez
11.
Organometallics ; 43(7): 774-786, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38606203

RESUMO

The Ir(I) complex [Ir(µ-Cl)(coe)2]2 (coe = cis-cyclooctene) is a catalyst precursor for benzene alkenylation using Cu(II) carboxylate salts. Using [Ir(µ-Cl)(coe)2]2, propenylbenzenes are formed from the reaction of benzene, propylene, and CuX2 (X = acetate, pivalate, or 2-ethylhexanoate). The Ir-catalyzed reactions selectively produce anti-Markovnikov products, trans-ß-methylstyrene, cis-ß-methylstyrene, and allylbenzene, along with minor amounts of the Markovnikov product, α-methylstyrene. The selectivity for the anti-Markovnikov products changed as the reaction progressed. For example, in a reaction that uses 240 equiv of Cu(OHex)2 (related to Ir), the selectivity for the anti-Markovnikov products increases from 18:1 at 3 h to 42:1 at 42 h with 30 psig of propylene at 150 °C. Studies of product stability have revealed that the increase in the selectivity for anti-Markovnikov products is not the result of an isomerization process or the selective decomposition of specific products. Rather, the change in selectivity correlates with the ratio of Cu(II) to Cu(I) in the solution, which decreases as the reaction progresses. We propose that the identity of the active catalyst changes as Cu(I) is accumulated, resulting in the formation of an active catalyst that is more selective for anti-Markovnikov products. Using a 4:1 Cu(I)/Cu(II) ratio at the start of the reaction, a 65(3):1 anti-Markovnikov/Markovnikov ratio is observed.

12.
J Hazard Mater ; 476: 134968, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901263

RESUMO

The widely used phenylurea herbicide isoproturon (IPU) and its residues can inhibit the growth of subsequently planted crops. However, reports on bioremediation of IPU-contaminated soil are scarce. In this study, Sphingobium sp. strain YBL2-gfp (a derivative of the IPU-degrading Sphingobium sp. strain YBL2 isolated by our lab) was constructed to bioremediate IPU-contaminated soil. In pot experiments, strain YBL2-gfp colonized the roots of wheat and eliminated IPU residues in the soil within 21 d, effectively alleviating its toxicity and restoring wheat growth. IPU treatment reduced the richness and diversity of soil bacteria, while inoculation YBL2-gfp mainly affected richness with less impact on diversity. The high concentrations of IPU and inoculation of YBL2-gfp alone reduced the soil microbial community connections, while bioaugmentation treatment enhanced the soil microbial community connections. Additionally, strain YBL2-gfp stimulated the metabolic capacity of the indigenous microbes, promoting the degradation of IPU and reducing the negative impact of high concentrations of IPU on microbial community. Taken together, this study offers relatively comprehensive insights into the practical application of bioaugmentation, demonstrating that strain YBL2 has the potential to remediate IPU-contaminated soils.

13.
Mater Today Bio ; 26: 101106, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38883421

RESUMO

Breaking the poor permeability of immune checkpoint inhibitors (ICIs) caused by the stromal barrier and reversing the immunosuppressive microenvironment are significant challenges in pancreatic cancer immunotherapy. In this study, we synthesized core-shell Fe3O4@TiO2 nanoparticles to act as carriers for loading VISTA monoclonal antibodies to form Fe3O4@TiO2@VISTAmAb (FTV). The nanoparticles are designed to target the overexpressed ICIs VISTA in pancreatic cancer, aiming to improve magnetic resonance imaging-guided sonodynamic therapy (SDT)-facilitated immunotherapy. Laser confocal microscopy and flow cytometry results demonstrate that FTV nanoparticles are specifically recognized and phagocytosed by Panc-2 cells. In vivo experiments reveal that ultrasound-triggered TiO2 SDT can induce tumor immunogenic cell death (ICD) and recruit T-cell infiltration within the tumor microenvironment by releasing damage-associated molecular patterns (DAMPs). Furthermore, ultrasound loosens the dense fibrous stroma surrounding the pancreatic tumor and increases vascular density, facilitating immune therapeutic efficiency. In summary, our study demonstrates that FTV nanoparticles hold great promise for synergistic SDT and immunotherapy in pancreatic cancer.

14.
Acta Biomater ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39067643

RESUMO

Crizotinib (CRZ), one of anaplastic lymphoma kinase tyrosine kinase inhibitors (ALK-TKIs), has emerged as a frontline treatment for ALK-positive (ALK+) lung adenocarcinoma. However, the overexpression of P-glycoprotein (P-gp, a mitochondrial adenosine triphosphate (ATP)-dependent protein) in lung adenocarcinoma lesions causes multidrug resistance and limits the efficacy of CRZ treatment. Herein, a mitochondria-targeting nanosystem, zeolitic imidazolate framework-90@indocyanine green (ZIF-90@ICG), was fabricated to intervene in mitochondria and overcome drug resistance. Due to the zinc ion (Zn2+) interference of ZIF-90 and the photodynamic therapy (PDT) of ICG, this nanosystem is well suited for damaging mitochondrial functions, thus downregulating the intracellular ATP level and inhibiting P-gp expression. In addition, systematic bioinformatics analysis revealed the upregulation of CD44 in CRZ-resistant cells. Therefore, hyaluronic acid (HA, a critical target ligand of CD44) was further modified on the surface of ZIF-90@ICG for active targeting. Overall, this ZIF-90@ICG nanosystem synergistically increased the intracellular accumulation of CRZ and reversed CRZ resistance to enhance its anticancer effect, which provides guidance for nanomedicine design to accurately target tumours and induce mitochondrial damage and represents a viable regimen for improving the prognosis of patients with ALK-TKIs resistance. STATEMENT OF SIGNIFICANCE: The original aim of our research was to combat multidrug resistance (MDR) in highly aggressive and lethal lymphoma kinase-positive (ALK+) lung adenocarcinoma. For this purpose, a cascade-targeted system was designed to overcome MDR, integrating lung adenocarcinoma-targeted hyaluronic acid (HA), mitochondrion-targeted zeolitic imidazolate framework-90 (ZIF-90), the clinically approved drug crizotinib (CRZ), and the fluorescence imaging agent/photosensitizer indocyanine green (ICG). Moreover, using a "two birds with one stone" strategy, ion interference and oxidative stress induced by ZIF-90 and photodynamic therapy (PDT), respectively, disrupt mitochondrial homeostasis, thus downregulating adenosine triphosphate (ATP) levels, inhibiting MDR-relevant P-glycoprotein (P-gp) expression and suppressing tumour metastasis. Overall, this research represents an attempt to implement the concept of MDR reversal and realize the trade-offs between MDR and therapeutic effectiveness.

15.
Sci Rep ; 13(1): 4232, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918599

RESUMO

Coal mining inevitably results in the movement of overlying strata, with the upward formation of the strata leading to surface subsidence, causing irreversible impact on the buildings, land, and ecological environment. The movement and deformation of the strata are controlled by the bearing structure in the overlying strata, whose failure results in the deformation and breakage of the overlying strata simultaneously. While studies have been conducted on the arch structure in unconsolidated layers (ASUL), its bearing performance has not been addressed. Therefore, this study develops a bearing mechanics model based on the morphological characteristics of the ASUL. The analytical expressions of the axial force, bending moment, and shear force of the cross-sectional area were determined using theoretical derivations. The model analysed the internal forces and showed the influence laws of the overlying load, horizontal pressure coefficient, and rise-to-span ratio of the ASUL. The failure criterion of the bearing was also further determined. The results indicated that with overlying and horizontal loads, the axial force and bending moment are symmetrically distributed, whereas the shear force is asymmetrically distributed. In addition, the axial force gradually increases from the dome to the base of the ASUL. Compared to the axial force and bending moment, the shear force has a lower impact on the stability of the ASUL. Most of the axial force and overlying load is received through the axial compression of the cross-section to maintain stability and play a bearing role on the overlying unconsolidated layers. As the overlying load, horizontal pressure coefficient, and rise-to-span ratio increase, the axial force, bending moment, and shearing force also increase gradually. This effect is more apparent at the dome, spandrel, and base of the ASUL. The stability of the dome and spandrel is key to the overall structural stability. Therefore, the failure criterion for the ASUL was determined based on the compression failure at the dome and spandrel. During the mining process of the working face, the ASUL served as load-bearing control for the overlying unconsolidated layers. Further, increasing width of the working face damages and shifts the base of the ASUL, resulting in compression failure at the dome and spandrel, further inducing dome lift and causing overall failure of the ASUL. Considering the aforementioned factors, a control method that reinforces the surface subsidence of the ASUL by 'one-time, upward, staged, and multiple-ground-drilling' compaction grouting has been proposed. During the mining process of the working face, the arch bead-like structure, combined with the ASUL, serves as the load-bearing control on the overlying strata and ground surface, reducing ASUL deformation in the unconsolidated layers, overlying strata, and ground surface. This process enables the controlling of ground subsidence of coal mining in thick unconsolidated layers.

16.
Sci Rep ; 13(1): 22722, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123647

RESUMO

Natural rock masses often contain heterogeneous structures with varying sizes, non-uniform distributions, and strengths, which influence the mechanical response characteristics and crack propagation modes under loading. Furthermore, heterogeneous structures can affect the stability of the rock mass, in serious cases, leading to geotechnical and mining engineering disasters. In the present work, a parallel-bond model (PBM)-based numerical simulation using Particle Flow Code (PFC) was carried out to study the strength and failure characteristics of sandstone specimens with heterogeneous structures under different loading rates. The results show that the peak strength increases with the increasing loading rate. In addition, all of the initial cracks occurred at the edges of the heterogeneous structures of specimens under different loading rates. The greater the loading rate, the greater the stress concentration degree at the edge of the heterogeneous structures, the greater the dissipated energy as the sandstone specimens with heterogeneous structures suffer damage, the more intense the acoustic emission activity, and the greater the damage degree of the specimens. The number of cracks generated in sandstone specimens with heterogeneous structures increases gradually with the increasing loading rate during the initial loading stage, and gradually decreases after the specimens are damaged. Cracks propagate and develop from the upper right region to the lower right region of the specimens, forming crack groups that rapidly penetrate the specimens, leading to failure. Under different loading rates, the final failure behavior of the sandstone specimens with heterogeneous structures changes from an inverted V-type to θ-type, then gradually evolves to O-type failure.

17.
Anal Cell Pathol (Amst) ; 2023: 9979291, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035018

RESUMO

Stress has become a universal biological phenomenon in the body, which leads to pathophysiological changes. However, the molecular network interactions between endoplasmic reticulum (ER) stress and ferroptosis under stressful conditions are not clear. For this purpose, we screened the gene expression profile of GSE173795 for intersection with ferroptosis genes and screened 68 differentially expressed genes (DEGs) (63 up-regulated, 5 down-regulated), mainly related to lipid and atherosclerosis, autophagy-animal, mitophagy-animal, focal adhesion, DNA replication, proteasome, oocyte meiosis, toll-like receptor signaling pathway, cell cycle, etc. Immune infiltration analysis revealed that stress resulted in decreased B cells memory, T cells CD8 and T cells CD4 memory resting, monocytes, macrophages M2, and increased B cells naive, T cells follicular helper, and macrophages M1. 19 core-DEGs (ASNS, TRIB3, ATF4, EIF2S1, CEBPG, RELA, HSPA5, DDIT3, STAT3, MAP3K5, HIF1A, HNF4A, MAPK14, HMOX1, CDKN1A, KRAS, SP1, SIRT1, EGFR) were screened, all of which were up-regulated DEGs. These biological processes and pathways were mainly involved in responding to ER stress, lipid and atherosclerosis, cellular response to stress, cellular response to chemical stress, and regulation of DNA-templated transcription in response to stress, etc. Spearman analysis did not find MAPK14 to be significantly associated with immune cells. Other core-DEGs were associated with immune cells, including B cells naive, T cells follicular helper, and monocytes. Based on core-DEGs, 283 miRNAs were predicted. Among the 22 miRNAs with highly cross-linked DEGs, 11 had upstream lncRNA, mainly targeting STAT3, SP1, CDKN1A, and SIRT1, and a total of 39 lncRNA were obtained. 85 potential drugs targeting 11 core-DEGs were identified and were expected to be potential immunotherapeutic agents for stress injury. Our experiments also confirmed that Liproxstatin-1 alleviates common cross-linked proteins between ER stress and ferroptosis. In conclusion, our study explored the molecular mechanisms and network interactions among stress-ER stress-ferroptosis from a novel perspective, which provides new research ideas for studying stressful injury.


Assuntos
Aterosclerose , Ferroptose , MicroRNAs , Proteína Quinase 14 Ativada por Mitógeno , RNA Longo não Codificante , Animais , Ferroptose/genética , Sirtuína 1 , Estresse do Retículo Endoplasmático/genética , Biologia Computacional/métodos , Lipídeos
18.
ACS Appl Mater Interfaces ; 15(17): 20800-20810, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37078779

RESUMO

Amplifying the intracellular reactive oxygen species (ROS) level remains an urgent challenge for efficient sonodynamic therapy (SDT) of tumors. Herein, by loading ginsenoside Rk1 with manganese-doped hollow titania (MHT), a Rk1@MHT sonosensitizer was conceived to strengthen the outcome of tumor SDT. The results verify that manganese-doping remarkably elevates the UV-visible absorption and decreases the bandgap energy of titania from 3.2 to 3.0 eV, which improves ROS production under ultrasonic irradiation. Immunofluorescence and Western blot analysis demonstrate that ginsenoside Rk1 can block the critical protein of the glutathione synthesis pathway, glutaminase, thus enhancing intracellular ROS by eliminating the endogenous glutathione-depleted pathway of ROS. Manganese-doping confers the nanoprobe T1-weighted MRI function (r2/r1 = 1.41). Moreover, the in vivo tests confirm that Rk1@MHT-based SDT eradicates liver cancer in tumor-bearing mice via dual upregulation of intracellular ROS production. In summary, our study provides a new strategy for designing high-performance sonosensitizer to achieve noninvasive cancer treatment.


Assuntos
Manganês , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Manganês/metabolismo , Linhagem Celular Tumoral , Regulação para Cima
19.
Appl Bionics Biomech ; 2022: 5360277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465181

RESUMO

Objective: Spinal surgery is gradually moving toward minimally invasive surgery, but there is still some lack of knowledge about the Unilateral Biportal Endoscopic (UBE) technique that has been hotly debated in recent years. We performed this systematic review and meta-analysis to clarify whether UBE is superior to percutaneous endoscopic lumbar discectomy (PELD) for relieving short-term postoperative pain and promoting functional recovery. Methods: Computer searches of PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wanfang databases were performed to search for studies on UBE versus PELD for single-segment lumbar disc herniation (ssLDH) from the time of database construction to Mar. 2022, and two investigators independently performed literature screening and data extraction, and evaluation of the quality of the included studies was observed as operation time, complications, and visual analogue scale (VAS) at each preoperative and postoperative stage as well as Oswestry Disability Index (ODI), and meta-analysis was performed by applying the Review Manager 5.4 software. Results: Meta-analysis showed that PELD had shorter operation time (MD = 35.36, 95% CI (4.67, 66.04), P = 0.02) and had lower VAS of back pain at 3 days postoperatively (MD = 0.62, 95% CI (0.04, 1.19), P = 0.04) compared to the UBE. However, there was no statistical significance between the two groups in terms of complications (MD = 2.53, 95% CI (0.40, 16.11), P = 0.33), VAS of back pain at 30 days postoperatively (MD = 0.05, 95% CI (-0.19, 0.28), P = 0.70), VAS of leg pain at 3 days postoperatively (MD = 0.21, 95% CI (-0.20, 0.61), P = 0.33), VAS of leg pain at 30 days postoperatively (MD = 0.09, 95% CI (-0.29, 0.46), P = 0.65), and ODI at 30 days postoperatively (MD = -0.81, 95% CI (-3.03, 1.41), P = 0.47). Conclusions: Current evidence suggests that both UBE and PELD are effective in relieving short-term postoperative pain and promoting functional recovery, and there is no difference in complications between them; UBE requires longer operation time, and PELD may be superior in relieving immediate postoperative pain. This trial is registered with PROSPERO ID: CRD42021287810.

20.
Leg Med (Tokyo) ; 54: 101982, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34687982

RESUMO

It is of great value to use bioinformatics methods to screen the core differentially expressed genes (DEGs) at different times after mouse skin and skeletal muscle wound, and to explore the relationship between them and the wound age. To this end, we downloaded the gene expression profiles of GSE140517 and GSE23006 from the NCBI-GEO gene database, used GEO2R online tools and Venn diagrams to screen out DEGs at different times and common-DEGs. The Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) channel analysis were carried out through the DAVID website respectively. Use STRING tool to build a Protein-protein Interaction (PPI) network, and use Cytoscape software to screen out core DEGs. The results showed that 13, 53, 43 and 13 core DEGs were screened out in the 6 h, 12 h, 24 h and common-DEGs group after wound. There were 7 core DEGs (Cxcl2, Cxcl3, Il1b, Ptgs2, Cxcl1, Timp1, Ccl3) in both the different time point and the common DEGs group. Meanwhile, there are 1 core DEGs (Ccl4) specifically expressed in the 6 h, 29 specifically expressed core DEGs (Isg20, Rtp4, Fcgr1, Ifi44, Trim30a, etc.) in the 12 h, and 18 specifically expressed core DEGs (Ccr7, Myd88, Igsf6, Ccr2, Gpsm3, etc.) in the 24 h, there are 6 core DEGs (Ccl4, Ccl7, Saa3, Cxcl5, Ccl2, Lcn2) specifically expressed in the common-DEGs group. The results of GO and KEGG analysis showed that the deterioration and exudation of the inflammatory response were the main cause at 6 h after wound. In addition to inflammation at 12 h and 24 h, the systemic immune response against viral and bacterial infections also gradually increased. In summary, the core DEGs selected in this study have combined characteristics, consistent with the healing function at the corresponding time point, and they are also has specificity and correlation with wound age. Therefore, by detecting the changes in the expression of co-expressed core DEGs at different times after wound, as well as detecting specific expressed DEGs at a specific time point or a specific period of time, it is very promising to provide help for the wound age estimation. However, limited by the GSE140517 gene expression profile in the database, only the difference in gene expression at different times within 24 h after wound was explored, and the research on the late wound age still needs to be further in-depth.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Animais , Ontologia Genética , Camundongos , Músculo Esquelético , Software
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