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1.
J Colloid Interface Sci ; 677(Pt B): 967-975, 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-39178675

RÉSUMÉ

While great efforts have been made to improve the electrocatalytic activity of existing materials toward hydrogen evolution reaction (HER), it is also importance for searching new type of nonprecious HER catalysts to realize the practical hydrogen evolution. Herein, we firstly report nanocrystalline transition metal tetraborides (TMB4, TM=W and Mo) as an efficient HER electrocatalyst has been synthesized by a single-step solid-state reaction. The optimized nanocrystalline WB4 exhibits an overpotential as low as 172 mV at 10 mA/cm2 and small Tafel slope of 63 mV/dec in 0.5 M H2SO4. Moreover, the nanocrystalline WB4 outperforms the commercial Pt/C at high current density region, confirming potential applications in industrially electrochemical water splitting. Theoretical study reveals that high intrinsic HER activity of WB4 is originated from its large work function that contributes to the weak hydrogen-adsorption energy. Therefore, this work provides new insights for development of robust nanocrystalline electrocatalysts for efficient HER.

2.
ACS Appl Mater Interfaces ; 16(33): 44094-44104, 2024 Aug 21.
Article de Anglais | MEDLINE | ID: mdl-39113176

RÉSUMÉ

Tissue-inspired layered structural hydrogel has attracted increasing attention in artificial muscle, wound healing, wearable electronics, and soft robots. Despite numerous efforts being devoted to developing various layered hydrogels, the rapid and efficient preparation of layered hydrogels remains challenging. Herein, inspired by the self-growth concept of living organisms, an interfacial catalytic self-growth strategy based on catechol chemistry-mediated self-catalytic system of preparing layered hydrogels is demonstrated. Typically, the tannic acid-metal ion (e.g., TA-Fe3+) complex embedded in the hydrogel substrate would catalytically trigger rapid solid-liquid interfacial polymerization to grow the hydrogel layer without bulk solution polymerization. The self-growth process can be finely controlled by changing the growth time, the molar ratio of Fe3+/TA, and so on. The strategy is applicable to prepare various layered hydrogels as well as complex layered hydrogel patterns, allowing the customization of the physicochemical properties of the hydrogel. In addition, the self-adhesive layered hydrogel was prepared and can be utilized as a wearable strain sensor to monitor physiological activities and human motions. The demonstrated interfacial catalytic self-growth strategy will provide a route to design and fabricate layered hydrogel materials.


Sujet(s)
Catéchols , Hydrogels , Tanins , Hydrogels/composition chimique , Hydrogels/synthèse chimique , Catéchols/composition chimique , Catalyse , Tanins/composition chimique , Humains , Dispositifs électroniques portables , Matériaux biomimétiques/composition chimique
3.
Huan Jing Ke Xue ; 45(8): 4980-4992, 2024 Aug 08.
Article de Chinois | MEDLINE | ID: mdl-39168713

RÉSUMÉ

Based on the entropy weight TOPSIS method to measure the development level of "zero-waste cities" in China from 2004 to 2021, the social network analysis method and spatial Durbin model were used to explore the spatial correlation network structure and impact mechanism of the development level of "zero-waste cities." The results showed that: ① The development level of "zero-waste cities" was generally on the decline in the whole country and the eastern and central regions. However, it was on the rise in the western regions. ② The spatial correlation of the development level of "zero-waste cities" presented a core-edge structure, with an overall upward trend in network density and a stable state in the overall network. ③ Beijing, Shanghai, Jiangsu, Zhejiang, Fujian, and Guangdong were at the center and dominant position of the network. ④ Beijing, Tianjin, Shanghai, and Jiangsu belonged to the "net benefit" sector; Zhejiang, Fujian, and Guangdong belonged to the "broker" sector; and the other provinces belonged to the "net overflow" sectors. ⑤ The level of urbanization, economic development, technological innovation, foreign investment, environmental regulations, government intervention, and population size had a significant impact on the development level of "zero-waste cities" in local or neighboring provinces, respectively. The research results can provide a reference for the proposal of policies for constructing and coordinating the development of "zero-waste cities" in various regions.

4.
Curr Issues Mol Biol ; 46(7): 7324-7338, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-39057075

RÉSUMÉ

Depression is the most common chronic mental illness and is characterized by low mood, insomnia, and affective disorders. However, its pathologic mechanisms remain unclear. Numerous studies have suggested that the ghrelin/GHSR system may be involved in the pathophysiologic process of depression. Ghrelin plays a dual role in experimental animals, increasing depressed behavior and decreasing anxiety. By combining several neuropeptides and traditional neurotransmitter systems to construct neural networks, this hormone modifies signals connected to depression. The present review focuses on the role of ghrelin in neuritogenesis, astrocyte protection, inflammatory factor production, and endocrine disruption in depression. Furthermore, ghrelin/GHSR can activate multiple signaling pathways, including cAMP/CREB/BDNF, PI3K/Akt, Jak2/STAT3, and p38-MAPK, to produce antidepressant effects, given which it is expected to become a potential therapeutic target for the treatment of depression.

5.
iScience ; 27(7): 110214, 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39040049

RÉSUMÉ

Two-dimensional (2D) materials, especially graphene-based materials, have important implications for tissue regeneration and biomedicine due to their large surface area, transport properties, ease of functionalization, biocompatibility, and adsorption capacity. Despite remarkable progress in the field of tissue regeneration and biomedicine, there are still problems such as unclear long-term stability, lack of in vivo experimental data, and detection accuracy. This paper reviews recent applications of graphene-based materials in tissue regeneration and biomedicine and discusses current issues and prospects for the development of graphene-based materials with respect to promoting the regeneration of tendons, neuronal cells, bone, chondrocytes, blood vessels, and skin, as well as applications in sensing, detection, anti-microbial activity, and targeted drug delivery.

6.
Tuberculosis (Edinb) ; 148: 102546, 2024 Jul 18.
Article de Anglais | MEDLINE | ID: mdl-39079219

RÉSUMÉ

BACKGROUND: Spinal Tuberculosis (STB) is a common cause of spinal malformation caused by extrapulmonary tuberculosis in developing countries, which seriously affects the quality of life of patients. It was found that the expression of miRNAs in macrophages was stable, specific and readily available after Mycobacterium tuberculosis (MTB) infection. Our research group determined the differential expression of miR-29a-3p in the vertebra of spinal tuberculosis and intervertebral disc lesions through RNAs chip screening and bioinformatics analysis. However, the specific molecular mechanism of miR-29a-3p in the inflammatory response of spinal tuberculosis remains unclear. OBJECTIVE: In this study, we mainly discussed the expression of miR-29a-3p in the focal tissue of spinal tuberculosis and the role and molecular mechanism of miR-29a-3p mediated by METTL3 in the inflammatory response of spinal tuberculosis. METHODS: The tissues of 15 cases of lumbar degenerative diseases and vertebral lesions of spinal tuberculosis were collected, and the THP-1 macrophage model infected by Mycobacterium tuberculosis was constructed, and verified by qRT-PCR, Western blot, fluorescence in situ hybridization, immunohistochemistry, Cell fluorescence and ELISA. RESULTS AND CONCLUSION: We found that the expression of miR-29a-3p was significantly down-regulated in the vertebral body and disc lesion tissues of patients with spinal tuberculosis. Overexpression of miR-29a-3p inhibited the levels of inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6), and inhibition of miR-29a-3p expression promoted the release of the levels of TNF-α, IL-1ß and IL-6 inflammatory factors. Our study also shows that knockout of methyltransferase 3 (METTL3) can significantly reduce the expression of miR-29a-3p and promote the release of pro-inflammatory cytokines in macrophages.

7.
Chin Med ; 19(1): 98, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-39010069

RÉSUMÉ

BACKGROUND: Heart failure (HF) is a complex cardiovascular syndrome with high mortality. Santalum album L. (SAL) is a traditional Chinese medicine broadly applied for various diseases treatment including HF. However, the potential active compounds and molecular mechanisms of SAL in HF treatment are not well understood. METHODS: The active compounds and possible mechanisms of action of SAL were analyzed and validated by a systems pharmacology framework and an ISO-induced mouse HF model. RESULTS: We initially confirmed that SAL alleviates heart damage in ISO-induced HF model. A total of 17 potentially active components in SAL were identified, with Luteolin (Lut) and Syringaldehyde (SYD) in SAL been identified as the most effective combination through probabilistic ensemble aggregation (PEA) analysis. These compounds, individually and in their combination (COMB), showed significant therapeutic effects on HF by targeting multiple pathways involved in anti-oxidation, anti-inflammation, and anti-apoptosis. The active ingredients in SAL effectively suppressed inflammatory mediators and pro-apoptotic proteins while enhancing the expression of anti-apoptotic factors and antioxidant markers. Furthermore, the synergistic effects of SAL on YAP and PI3K-AKT signaling pathways were further elucidated. CONCLUSIONS: Mechanistically, the anti-HF effect of SAL is responsible for the synergistic effect of anti-inflammation, antioxidation and anti-apoptosis, delineating a multi-targeted therapeutic strategy for HF.

8.
Int J Biol Macromol ; 269(Pt 1): 132097, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38710249

RÉSUMÉ

Biodegradable polymer blends filled with rod-like polysaccharide nanocrystals have attracted much attention because each component in this type of ternary composites is biodegradable, and the final properties are more easily tailored comparing to those of binary composites. In this work, chitin nanocrystals (ChNCs) were used as nanofiller for the biodegradable poly(ε-caprolactone) (PCL)/polylactide (PLA) immiscible blend to prepare ternary composites for a crystallization study. The results revealed that the crystallization behavior of PCL/PLA blend matrices strongly depended on the surface properties of ChNCs. Non-modified ChNCs and modified ChNCs played completely different roles during crystallization of the ternary systems: the former was inert filler, while the latter acted as anti-nucleator to the PCL phase. This alteration was resulted from the improved ChNC-PCL affinity after modification of ChNCs, which was due to the 'interfacial dilution effect' and the preferential dispersion of ChNCs. This work presents a unique perspective on the nucleation role of ChNCs in the crystallization of immiscible PCL/PLA blends, and opens up a new application scenario for ChNCs as anti-nucleator.


Sujet(s)
Chitine , Cristallisation , Interactions hydrophobes et hydrophiles , Nanoparticules , Polyesters , Polyesters/composition chimique , Chitine/composition chimique , Nanoparticules/composition chimique
9.
JOR Spine ; 7(2): e1331, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38606423

RÉSUMÉ

Objectives: The objective of this study is to evaluate the value of S100-A8 protein as a diagnostic marker for spinal tuberculosis and to explore its role in the potential pathogenesis of spinal tuberculosis (STB). Methods: The peripheral blood of 100 spinal tuberculosis patients admitted to the General Hospital of Ningxia Medical University from September 2018 to June 2021 were collected as the observation group, and the peripheral blood of 30 healthy medical examiners were collected as the control group. Three samples from the observation group and three samples from the control group were selected for proteomics detection and screening of differential proteins. Kyoto Encyclopedia of Genes (KEGG) was used to enrich and analyze related signaling pathways to confirm the target protein. The serum expression levels of the target proteins were determined and compared between the two groups using enzyme-linked immunosorbent assay (ELISA). Statistical methods were used to evaluate the value of target protein as a diagnostic marker for STB. A macrophage model of Mycobacterium tuberculosis infection was constructed and S100-A8 small interfering RNA was used to investigate the molecular mechanism of the target protein. Results: S100-A8 protein has the value of diagnosing spinal tuberculosis (AUC = 0.931, p < 0.001), and the expression level in the peripheral blood of the observation group (59.04 ± 19.37 ng/mL) was significantly higher than that of the control group (43.16 ± 10.07 ng/mL) (p < 0.05). S100-A8 protein expression showed a significant positive correlation with both CRP and ESR values (p < 0.01). Its AUCs for combined bacteriological detection, T-SPOT results, diagnostic imaging, antacid staining results, and pathological results were 0.705 (p < 0.05), 0.754 (p < 0.01), 0.716 (p < 0.01), 0.656 (p < 0.05), and 0.681 (p < 0.01), respectively. Lack of S100-A8 leads to a significant decrease in the expression levels of TLR4 and IL-17A in infected macrophages. Conclusion: S100-A8 protein is differentially expressed in the peripheral blood of patients with spinal tuberculosis and healthy individuals and may be a novel candidate biomarker for the diagnosis of spinal tuberculosis. The feedback loop on the S100-A8-TLR4-IL-17A axis may play an important role in the inflammatory mechanism of spinal tuberculosis.

10.
Angew Chem Int Ed Engl ; 63(28): e202405895, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38660927

RÉSUMÉ

Light-driven micro/nanorobots (LMNRs) are tiny, untethered machines with great potential in fields like precision medicine, nano manufacturing, and various other domains. However, their practicality hinges on developing light-manipulation strategies that combine versatile functionalities, flexible design options, and precise controllability. Our study introduces an innovative approach to construct micro/nanorobots (MNRs) by utilizing micro/nanomotors as fundamental building blocks. Inspired by silicon Metal-Insulator-Semiconductor (MIS) solar cell principles, we design a new type of optomagnetic hybrid micromotors (OHMs). These OHMs have been skillfully optimized with integrated magnetic constituent, resulting in efficient light propulsion, precise magnetic navigation, and the potential for controlled assembly. One of the key features of the OHMs is their ability to exhibit diverse motion modes influenced by fracture surfaces and interactions with the environment, streamlining cargo conveyance along "micro expressway"-the predesigned microchannels. Further enhancing their versatility, a template-guided assembly strategy facilitates the assembly of these micromotors into functional microrobots, encompassing various configurations such as "V-shaped", "N-shaped", and 3D structured microrobots. The heightened capabilities of these microrobots, underscore the innovative potential inherent in hybrid micromotor design and assembly, which provides a foundational platform for the realization of multi-component microrobots. Our work moves a step toward forthcoming microrobotic entities boasting advanced functionalities.

11.
Poult Sci ; 103(5): 103587, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38479099

RÉSUMÉ

Trichomonas gallinae (T. gallinae) is a globally distributed protozoan parasite and could cause serious damage to the pigeon industry. MiRNAs have important roles in regulating parasite infection, but its impacts on T. gallinae resistance have rarely been reported. In the present study, we identified a new miRNA (novel-miR-741) and its predicted target OTU deubiquitinase 1 (OTUD1) that might be associated with immunity to T. gallinae in pigeon. Novel-miR-741 and OTUD1 over-expression vectors and interference vectors were constructed. Results from dual luciferase activity assay demonstrated that OTUD1 was a downstream target of novel-miR-741. The Cell Counting Kit-8 and apoptosis assays showed that novel-miR-741 inhibited the proliferation and promoted apoptosis of pigeon crop fibroblasts. Meanwhile, mRNA levels of OTUD1 were significantly reduced in novel-miR-741 mimic-transfected fibroblasts, while mRNA levels of OTUD1 were significantly increased in the novel-miR-741 inhibitor-transfected fibroblasts. The regulatory roles of si-OTUD1 on fibroblasts proliferation, apoptosis, and migration were similar to novel-miR-741 mimic. Our findings demonstrated that novel-miR-741 inhibited the proliferation, and migration of crop fibroblasts, while OTUD1 promoted the proliferation and migration of crop fibroblasts. Therefore, the regulation of OTUD1 by novel-miR-741 was proposed as a potential therapeutic strategy for T. gallinae.


Sujet(s)
Apoptose , Prolifération cellulaire , Columbidae , Fibroblastes , microARN , microARN/génétique , microARN/métabolisme , Animaux , Fibroblastes/physiologie , Columbidae/physiologie , Protéines aviaires/génétique , Protéines aviaires/métabolisme
12.
Arch Insect Biochem Physiol ; 115(1): e22086, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38288496

RÉSUMÉ

The mitochondrial gene order in Thysanoptera is notably distinct and highly rearranged, with each species exhibiting its own unique arrangement. To elucidate the relationship between gene rearrangements and phylogeny, the complete mitochondrial genome (mitogenome) of the wheat pest, Aptinothrips stylifer, was sequenced and assembled, spanning a total length of 16,033 bp. Compared with the ancestral arthropod mitogenome, significant rearrangement differences were evident in A. stylifer, whereas the gene order between A. stylifer and Anaphothrips obscurus was similar. Phylogenetic trees were reconstructed based on all 13 protein-coding gene sequences using Bayesian inference and maximum-likelihood methods, both yielding similar topological structures. Notably, A. stylifer was robustly clustered with A. obscurus, affirming its classification within Anaphothrips genus group. This exemplifies the potential correlation between gene rearrangements and phylogeny in the Thripidae family. Additionally, the mitogenome of A. stylifer exhibited several atypical features, including: (1) Three putative control regions (CRs) in close proximity, with CR2 and CR3 displaying partial similarity, and CR1 differing in base composition; (2) Two transfer RNAs (tRNAs), trnS1 and trnV, lacking the DHU arm; (3) Two ribosomal RNA (rRNA) genes inverted and positioned distant from each other; (4) Negative AT and GC skew (AT skew = -0.001, GC skew = -0.077); (5) One transposition (nad6), one inverse transposition (trnQ), four inversions (trnF, trnH, trnC, and gene block nad1-trnL1-rrnL-trnV-rrnS), and four tandem duplication random loss events; and (6) Two protein-coding genes, nad2 and atp8, terminated with an incomplete stop codon "T".


Sujet(s)
Génome mitochondrial , Thysanoptera , Animaux , Phylogenèse , Thysanoptera/génétique , Triticum/génétique , Théorème de Bayes
13.
Adv Mater ; 36(8): e2305632, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-37805826

RÉSUMÉ

Optically controlled neuromodulation is a promising approach for basic research of neural circuits and the clinical treatment of neurological diseases. However, developing a non-invasive and well-controllable system to deliver accurate and effective neural stimulation is challenging. Micro/nanorobots have shown great potential in various biomedical applications because of their precise controllability. Here, a magnetically-manipulated optoelectronic hybrid microrobot (MOHR) is presented for optically targeted non-genetic neuromodulation. By integrating the magnetic component into the metal-insulator-semiconductor junction design, the MOHR has excellent magnetic controllability and optoelectronic properties. The MOHR displays a variety of magnetic manipulation modes that enables precise and efficient navigation in different biofluids. Furthermore, the MOHR could achieve precision neuromodulation at the single-cell level because of its accurate targeting ability. This neuromodulation is achieved by the MOHR's photoelectric response to visible light irradiation, which enhances the excitability of the targeted cells. Finally, it is shown that the well-controllable MOHRs effectively restore neuronal activity in neurons damaged by ß-amyloid, a pathogenic agent of Alzheimer's disease. By coupling precise controllability with efficient optoelectronic properties, the hybrid microrobot system is a promising strategy for targeted on-demand optical neuromodulation.


Sujet(s)
Lumière , Magnétisme
14.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37934673

RÉSUMÉ

Deinococcus saudiensis YIM F302T was compared with Deinococcus soli N5T to examine the taxonomic relationship between the two type strains. The 16S rRNA gene sequence of D. saudiensis YIM F302T showed high similarity (99.9 %) to that of D. soli N5T. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the two strains formed a tight cluster within the genus Deinococcus. A draft genomic comparison between the two strains revealed average nucleotide identity values of 96.8-97.9 % and a digital DNA-DNA hybridization estimate of 80.7±1.9 %, strongly indicating that the two strains represented a single species. Based on the combined phylogenetic, genomic and phenotypic characterization presented here, we propose D. saudiensis as a later heterotypic synonym of D. soli N5T.


Sujet(s)
Deinococcus , Phylogenèse , Deinococcus/génétique , ARN ribosomique 16S/génétique , Analyse de séquence d'ADN , ADN bactérien/génétique , Techniques de typage bactérien , Acides gras/composition chimique , Composition en bases nucléiques , Hybridation d'acides nucléiques
15.
Appl Opt ; 62(15): 3967-3975, 2023 May 20.
Article de Anglais | MEDLINE | ID: mdl-37706707

RÉSUMÉ

In this paper, we implement integrated magnetic flux concentrators (MFCs) combined with a multi-frequency modulation method to achieve high-magnetic-detection sensitivity using a nuclear spin on the solid nuclear spin in diamonds. First, we excited the nuclear spin in diamonds using a continuous-wave technique, and a linewidth of 1.37 MHz and frequency resolution of 79 Hz were successfully obtained, which is reduced by one order of the linewidth, and increased by 56 times in frequency resolution compared to that excited by an electron spin. The integrated high-permeability MFC was designed to magnify the magnetic field near the diamond, with a magnification of 9.63 times. Then, the multi-frequency modulation technique was used to fully excite the hyperfine energy level of Nitrogen Vacancy (NV) centers along the four axes on the diamond with MFC, and magnetic detection sensitivity of 250p T/H z 1/2 was realized. These techniques should allow designing an integrated NV magnetometer with high sensitivity in a small volume.

16.
Nanomicro Lett ; 15(1): 174, 2023 Jul 07.
Article de Anglais | MEDLINE | ID: mdl-37420043

RÉSUMÉ

Composite organohydrogels have been widely used in wearable electronics. However, it remains a great challenge to develop mechanically robust and multifunctional composite organohydrogels with good dispersion of nanofillers and strong interfacial interactions. Here, multifunctional nanofiber composite reinforced organohydrogels (NCROs) are prepared. The NCRO with a sandwich-like structure possesses excellent multi-level interfacial bonding. Simultaneously, the synergistic strengthening and toughening mechanism at three different length scales endow the NCRO with outstanding mechanical properties with a tensile strength (up to 7.38 ± 0.24 MPa), fracture strain (up to 941 ± 17%), toughness (up to 31.59 ± 1.53 MJ m-3) and fracture energy (up to 5.41 ± 0.63 kJ m-2). Moreover, the NCRO can be used for high performance electromagnetic interference shielding and strain sensing due to its high conductivity and excellent environmental tolerance such as anti-freezing performance. Remarkably, owing to the organohydrogel stabilized conductive network, the NCRO exhibits superior long-term sensing stability and durability compared to the nanofiber composite itself. This work provides new ideas for the design of high-strength, tough, stretchable, anti-freezing and conductive organohydrogels with potential applications in multifunctional and wearable electronics.

17.
Nat Commun ; 14(1): 3537, 2023 06 15.
Article de Anglais | MEDLINE | ID: mdl-37322000

RÉSUMÉ

The SARS-CoV-2 Omicron variant evades most currently approved neutralizing antibodies (nAbs) and caused drastic decrease of plasma neutralizing activity elicited by vaccination or prior infection, urging the need for the development of pan-variant antivirals. Breakthrough infection induces a hybrid immunological response with potentially broad, potent and durable protection against variants, therefore, convalescent plasma from breakthrough infection may provide a broadened repertoire for identifying elite nAbs. We performed single-cell RNA sequencing (scRNA-seq) and BCR sequencing (scBCR-seq) of B cells from BA.1 breakthrough-infected patients who received 2 or 3 previous doses of inactivated vaccine. Elite nAbs, mainly derived from the IGHV2-5 and IGHV3-66/53 germlines, showed potent neutralizing activity across Wuhan-Hu-1, Delta, Omicron sublineages BA.1 and BA.2 at picomolar NT50 values. Cryo-EM analysis revealed diverse modes of spike recognition and guides the design of cocktail therapy. A single injection of paired antibodies cocktail provided potent protection in the K18-hACE2 transgenic female mouse model of SARS-CoV-2 infection.


Sujet(s)
COVID-19 , SARS-CoV-2 , Femelle , Animaux , Souris , SARS-CoV-2/génétique , Réinfections , Sérothérapie COVID-19 , Anticorps neutralisants , Souris transgéniques , Anticorps antiviraux
18.
Materials (Basel) ; 16(5)2023 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-36902875

RÉSUMÉ

Creep deformation is an important aspect of magnesium phosphate cement (MPC) used as a structural material. In this study, the shrinkage and creep deformation behaviors of three different MPC concretes were observed for 550 days. The mechanical properties, phase composition, pore structure, and microstructure of MPC concretes after shrinkage and creep tests were investigated. The results showed that the shrinkage and creep strains of MPC concretes stabilized in the ranges of -140 to -170 µÎµ and -200 to -240 µÎµ, respectively. The low water-to-binder ratio and the formation of crystalline struvite were responsible for such low deformation. The creep strain had almost no effect on the phase composition; however, it increased the crystal size of struvite and reduced the porosity, especially the volume of pores with diameters <20 nm and >200 nm. The modification of struvite and densification of microstructure led to an improvement in both compressive strength and splitting tensile strength.

19.
Molecules ; 27(24)2022 Dec 12.
Article de Anglais | MEDLINE | ID: mdl-36557960

RÉSUMÉ

The PROteolysis TArgeting Chimeras (PROTACs) is an innovative technique for the selective degradation of target proteins via the ubiquitin-proteasome system. Compared with traditional protein inhibitor drugs, PROTACs exhibit advantages in the efficacy and selectivity of and in overcoming drug resistance in cancer therapy, providing new insights into the discovery of anti-cancer drugs. In the last two decades, many PROTAC molecules have been developed to induce the degradation of cancer-related targets, and they have been subjected to clinical trials. Here, we comprehensively review the historical milestones and latest updates in PROTAC technology. We focus on the structures and mechanisms of PROTACs and their application in targeting tumor-related targets. We have listed several representative PROTACs based on CRBN, VHL, MDM2, or cIAP1 E3 ligases, and PROTACs that are undergoing anti-cancer clinical trials. In addition, the limitations of the current research, as well as the future research directions are described to improve the PROTAC design and development for cancer therapy.


Sujet(s)
Antinéoplasiques , Tumeurs , Humains , Protéolyse , Proteasome endopeptidase complex/métabolisme , Ubiquitine/métabolisme , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Tumeurs/traitement médicamenteux
20.
Arch Microbiol ; 204(10): 638, 2022 Sep 21.
Article de Anglais | MEDLINE | ID: mdl-36131209

RÉSUMÉ

A novel marine Gram-stain-negative, aerobic, rod-shaped bacterium, designated as strain PS1T, was isolated from the deep-sea sediments of the Mariana Trench and characterized phylogenetically and phenotypically. Bacterial optimal growth occurred at 35 °C (ranging 10-45 °C), pH 6 (ranging pH 5-10) and with 11% (w/v) NaCl (ranging 0-17%). The 16S rRNA gene sequence similarity results revealed that strain PS1T was most closely related to Pseudomonas stutzeri ATCC 17588T, Pseudomonas nitrititolerans GL14T, Pseudomonas zhaodongensis NEAU-ST5-21T, Pseudomonas xanthomarina DSM 18231T and Pseudomonas kunmingensis HL22-2T with 98.3-98.7%. The digital DNA-DNA hybridization values and the average nucleotide identity between strain PS1T and the reference strains were 20.4-40.1% and 78.7-79.4%, respectively. The major respiratory quinone is ubiquinone Q-9. The major polar lipids were phosphatidylethanolamine, diphosphatidyglycerol, phosphatidylglycerol, phosphatidylcholine, aminoglycolipid, two unidentified glycolipids and one unidentified lipid. The predominant cellular fatty acids of strain PS1T were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω7c and/or C16:1ω6c), C16:0 and cyclo-C19:0 ω8c. The G + C content of the genomic DNA was 63.0%. The combined genotypic and phenotypic data indicated that strain PS1T represents a novel species of the genus Pseudomonas, for which the name Pseudomonas marianensis sp. nov. is proposed, with the type strain PS1T (= DSM 112238T = MCCC 1K05112T).


Sujet(s)
Phosphatidyléthanolamine , Chlorure de sodium , Ancitabine , Techniques de typage bactérien , ADN bactérien/composition chimique , ADN bactérien/génétique , Acides gras/analyse , Glycolipides/composition chimique , Nucléotides , Phosphatidylcholines , Phosphatidylglycérol , Phospholipides/analyse , Phylogenèse , Pseudomonas , ARN ribosomique 16S/génétique , Analyse de séquence d'ADN , Ubiquinones/composition chimique
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