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Several cellular processes, including the recovery of misfolded proteins, the folding of polypeptide chains, transit of polypeptides across the membrane, construction and disassembly of protein complexes, and modulation of protein control, are carried out by DnaJ homolog subfamily A member 1 (DNAJA1), which belongs to the DnaJ heat-shock protein family. It is unknown if DNAJA1 regulates the production of milk in bovine mammary epithelium cells (BMECs). Methionine and leucine increased DNAJA1 expression and nuclear location, as seen by us. In contrast to DNAJA1 knockdown, overexpression of DNAJA1 boosted the production of milk proteins and fats as well as mammalian target of rapamycin (mTOR) and sterol regulatory element binding protein-1c (SREBP-1c). As a result of amino acids, mTOR and SREBP-1c gene expression are stimulated, and DNAJA1 is a positive regulator of BMECs' amino acid-induced controlled milk protein and fat production.
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Células Epiteliais , Proteínas do Leite , Animais , Bovinos , Aminoácidos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Serina-Treonina Quinases TORRESUMO
Heterotopic bone occurs after burns, trauma and major orthopedic surgery, which cannot be completely cured by current treatments. The development of new treatments requires more in-depth research into the mechanism of HO. Available evidence suggests that miR-21-5p plays an important role in bone formation. However, its mechanism in traumatic HO is still unclear. First, we identified exosomes extracted from L6 cells using TEM observation of the structure and western blotting detection of the surface marker CD63. Regulation effect of HIF-1α to miR-21-5p was confirmed by q-PCR assay. Then we co-cultured L6 cells with ASCs and performed alizarin red staining and ALP detection. Overexpression of miR-21-5p upregulated BMP4, p-smad1/5/8, OCN and OPN, which suggests the BMP4-smad signaling pathway may be involved in miR-21-5p regulation of osteogenic differentiation of ASCs. Finally inâ vivo experiments showed that miR-21-5p exosomes promoted ectopic formation in traumatized mice. This study confirms that HIF-1α could modulate miR-21-5p exosomes to promote post-traumatic ectopic bone formation by inducing ASCs cell differentiation. Our study reveals the mechanisms of miR-21-5p in ectopic ossification formation after trauma.
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Exossomos , MicroRNAs , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese , Exossomos/metabolismo , Diferenciação Celular , Células CultivadasRESUMO
Typeâ I main-chain polyrotaxanes (PRs) with multiple wheels threaded onto the axle are widely employed to design slide-ring materials. However, Typeâ II main-chain PRs with axles threading into the macrocycles on the polymer backbones have rarely been studied, although they feature special topological structures and dynamic characteristics. Herein, we report the design and preparation of Typeâ II main-chain PR-based mechanically interlocked networks (PRMINs), based on which the relationship between microscopic motion of mechanical bonds on the PRs and macroscopic mechanical performance of materials has been revealed. The representative PRMIN-2 exhibits a robust feature in tensile tests with high stretchability (1680 %) and toughness (47.5â MJ/m3). Moreover, it also has good puncture performance with puncture energy of 22.0â mJ. Detailed rheological measurements and coarse-grained molecular dynamics (CGMD) simulation reveal that the embedded multiple [2]rotaxane mechanical bonds on the PR backbones of PRMINs could undergo a synergistic long-range sliding motion under external force, with the introduction of collective dangling chains into the network. As a result, the synchronized motions of coherent PR chains can be readily activated to accommodate network deformation and efficiently dissipate energy, thereby leading to enhanced mechanical performances of PRMINs.
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Polymer electrolytes play a crucial role in advancing rechargeable magnesium batteries (RMBs) owing to their exceptional characteristics, including high flexibility, superior interface compatibility, broad electrochemical stability window, and enhanced safety features. Despite these advantages, research in this domain remains nascent, plagued by single preparation approaches and challenges associated with the compatibility between polymer electrolytes and Mg metal anode. In this study, we present a novel synthesis strategy to fabricate a glycerol α,α'-diallyl ether-3,6-dioxa-1,8-octanedithiol-based composite gel polymer electrolyte supported by glass fiber substrate (GDT@GF CGPE) through anion modification and thiol-ene click chemistry polymerization. The developed route exhibits novelty and high efficiency, leading to the production of GDT@GF CGPEs featuring exceptional mechanical properties, heightened ionic conductivity, elevated Mg2+ transference number, and commendable compatibility with Mg anode. The assembled modified Mo6S8||GDT@GF||Mg cells exhibit outstanding performance across a wide temperature range and address critical safety concerns, showcasing the potential for applications under extreme conditions. Our innovative preparation strategy offers a promising avenue for the advancement of polymer electrolytes in high-performance rechargeable magnesium batteries, while also opens up possibilities for future large-scale applications and the development of flexible electronic devices.
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Adaptive bionic self-correcting behavior offers an attractive property for chemical systems. Here, based on the dynamic feature of imine formation, we propose a solvent-responsive strategy for smart switching between an amorphous ionic polyimine membrane and a crystalline organic molecule cage without the addition of other building blocks. To adapt to solvent environmental constraints, the aldehyde and amine components undergo self-correction to form a polymer network or a molecular cage. Studies have shown that the amorphous film can be switched in acetonitrile to generate a discrete cage with bright birefringence under polarized light. Conversely, the membrane from the cage crystal conversion can be regained in ethanol. Such a membrane-cage interconversion can be cycled continuously at least 5 times by switching the two solvents. This work builds a bridge between the polymer network and crystalline molecules and offers prospects for smart dynamic materials.
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PURPOSE: To evaluate the effectiveness of fluoroscopy guided transpedicular abscess infusion and drainage in thoracic-lumbar spondylitis with prevertebral abscess. METHODS: We retrospectively reviewed 14 patients with infectious spondylitis with prevertebral abscesses from January 2019 to December 2022. All patients underwent fluoroscopy guided transpedicular abscess infusion and drainage. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), visual analog scale (VAS), Macnab criteria, and magnetic resonance imaging (MRI) were compared before and after the operation to evaluate clinical outcomes. RESULTS: Among the 14 patients with prevertebral abscesses, 64.29% (9/14) involved the lumbar spine and 35.71% (5/14) involved the thoracic spine. The ESR, CRP, and VAS scores decreased from 87.34 ± 9.21, 93.01 ± 11.17, and 8.38 ± 0.97 preoperatively to 12.35 ± 1.61, 8.52 ± 1.19, and 2.02 ± 0.64 at the final follow-up, respectively. MRI at the final follow-up showed the disappearance of the prevertebral abscess compared with that in the preoperative group (66.95 ± 12.63 mm in diameter). Ten patients achieved an "excellent" outcome, while the remaining four patients obtained a "good" outcome according to the Macnab criteria. CONCLUSION: Fluoroscopy guided transpedicular abscess infusion and drainage is a safe and minimally invasive procedure for the management of thoracic-lumbar spondylitis with a prevertebral abscess.
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Fusão Vertebral , Espondilite , Humanos , Abscesso/diagnóstico por imagem , Abscesso/cirurgia , Estudos Retrospectivos , Espondilite/diagnóstico por imagem , Espondilite/cirurgia , Drenagem/métodos , Fluoroscopia , Vértebras Lombares/cirurgia , Resultado do TratamentoRESUMO
Mechanical bonds have been utilized as promising motifs to construct mechanically interlocked aerogels (MIAs) with mechanical adaptivity and multifunctionality. However, fabricating such aerogels with not only precise chemical structures but also dynamic features remains challenging. Herein, we present MIAs carrying dense [2]rotaxane units, which bestow both the stability and flexibility of the aerogel network. Owing to the stable chemical structure of a [2]rotaxane, MIAs possessing a precise and full-scale mechanically interlocked network could be fabricated with the aid of diverse solvents. In addition, the dynamic nature of the [2]rotaxane resulted in morphologies and mechanical performances of the MIAs that can be dramatically modulated under chemical stimuli. We hope that the structure-property relationship in MIAs will facilitate the development of mechanically interlocked materials and provide novel opportunities toward constructing smart materials with multifunctionalities.
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Zinc (Zn) metal is considered a potential anode owing to its high theoretical capacity, safety, and low cost. However, the dendrites and corresponding side reactions in aqueous electrolytes hinder their further development in environmentally-friendly energy storage. Herein, ion-affiliative cellulose acetate (CA) coating with Zn(CF3 SO3 )2 is constructed on Zn anode (CAZ@Zn). Owing to the complexation effect between the polar ester group (CO) and Zn salt (Zn2+ ), the CAZ polymer coating enhances the hydrophilicity of the Zn anode and reduces the interfacial resistance, allowing the rapid Zn2+ diffusion and homogenizing the Zn deposition in an aqueous electrolyte to suppress zinc dendrite formation and growth. Therefore, the symmetric CAZ@Zn//CAZ@Zn battery achieves reversible plating/stripping over 2800 h at 1 mA cm-2 with 1 mAh cm-2 , about sevenfold higher than bare Zn. The full cell fabricated with an optimized Zn anode and the NH4 V4 O10 cathode achieves substantially stable performance, superior to that of bare Zn. This work provides a straightforward, effective, and scalable method to suppress the zinc dendrites and corresponding side reactions for aqueous Zn-ions batteries.
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Ésteres , Zinco , Acetatos , Celulose/análogos & derivados , Eletrodos , Eletrólitos , Metais , PolímerosRESUMO
The cyclopeptide alkaloids are cyclic depsipeptides incorporating cyclophanes with polyamide units 13-, 14- and 15-membered macrocyclic systems. Although various pharmacological activities have been ascribed to cyclopeptide alkaloids from plants of the Rhamnacea family, these studies have been hampered by their low availability due to the lack of reasonable amounts distributed in nature. Therefore, novel and efficient synthetic approaches should be an important aim, which inspired us to examine how to diversely construct the unique structures of this type of natural products. In this account, several typical strategies are presented in terms of efficient, stereocontrolled and regioselective synthesis of cyclopeptide alkaloids.
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Alcaloides/síntese química , Produtos Biológicos/síntese química , Compostos Macrocíclicos/química , Peptídeos Cíclicos/síntese química , Alcaloides/química , Produtos Biológicos/química , Conformação Molecular , Peptídeos Cíclicos/química , Rhamnaceae/química , EstereoisomerismoRESUMO
We have previously reported the unique features of dimeric bisaminoquinolines as anticancer agents and have identified their cellular target as PPT1, a protein palmitoyl-thioesterase. We now report a systematic study on the role of the linker in these constructs, both with respect to the distance between the heterocycles, the linker hydrophobicity and the methylation status (primary vs. secondary vs. tertiary) of the central nitrogen atom on the observed biological activity.
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Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Aminoquinolinas/síntese química , Antineoplásicos/síntese química , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Membrana/antagonistas & inibidores , Estrutura Molecular , Tioléster Hidrolases/antagonistas & inibidoresRESUMO
Due to the low cost, high element abundance and intrinsic safety, potassium-ion batteries (KIBs) have attracted a surge of interest in recent years. Currently, the key challenge and obstacle to the development of KIBs is to find suitable anode materials with large capacity, high rate capability and small lattice changes during the charge/discharge process. MXenes with excellent energy storage properties are promising anode materials for KIBs and their energy performance largely depends on the surface termination. Here, two-dimensional O- and S-terminated V2C MXene anode materials are designed to model high performance potassium-ion batteries. Using first-principles calculations, the structural properties and potential battery performance in KIBs of V2CO2 and V2CS2 are systematically investigated. The inherent metallic nature, a small diffusion barrier, a low average open circuit voltage, and a high theoretical specific capacity (489.93 mA h g-1 of V2CO2 and 200.24 mA h g-1 of V2CS2) demonstrate that both of them are ideal anode materials for KIBs. Meanwhile, we also investigated the mechanism of the difference in energy performance between V2CO2 and V2CS2 at atomic and electronic levels, in other words, the energy performance difference introduced by surface O- and S-terminations.
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As the rapid development of high-end intelligent equipment continues, the design requirements for crack and strain monitoring equipment are increasing daily. In this paper, a decoupled monitoring method for strain and cracks based on a multilayer patch antenna sensor is studied. First, the monitoring principle for strain and crack decoupling is analyzed. Second, the design method for the multilayer patch antenna sensor is studied, and the hierarchical arrangement, patch size, substrate layer thickness, and feeding line structure are designed on the basis of this method. A quarter-wavelength impedance converter is designed to perform impedance matching and optimize the resonant frequency information. The effects of strain and crack propagation on the resonant frequency of the patch antenna are analyzed through simulations, and the decoupled monitoring method for the structural stress state and crack propagation is discussed. Lastly, the feasibility of decoupled monitoring of strain and cracks is verified experimentally. The results of the theoretical analysis, simulations, and experiments show that the proposed patch antenna sensor based on the multilayer structure can realize decoupled monitoring of strain and cracks in the structure, and the sensor has broad application prospects.
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1,2,3-Benzotriazoles could undergo ring cleavage to form ortho-amino arenediazonium or α-diazo-imine species via a Dimroth-type equilibrium. Historically, the synthetic potential of this unique reactivity had remained underdeveloped. Recently, some new strategies have been developed to effect the ring-opening chemistry of benzotriazoles in more practical manners. A wide range of conceptually novel and synthetically useful reactions have been developed, which enable the access to diverse valuable heterocycles and ortho-amino arene derivatives. As one of the players in this field, our group has also contributed a series of intriguing transition-metal-catalyzed denitrogenative functionalizations of benzotriazoles. In this account, we aim to provide an overview of the ring-opening chemistry of benzotriazoles, with a focus on relevant works published in the past decade. In order to show a whole picture of the research field, some pioneering works in its developing history will also be discussed briefly.
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Thermal energy harvesting from the ambient environment through thermoelectric nanogenerators (TEGs) is an ideal way to realize self-powered operation of electronics, and even relieve the energy crisis and environmental degradation. As one of the most significant energy-related technologies, TEGs have exhibited excellent thermoelectric performance and played an increasingly important role in harvesting and converting heat into electric energy, gradually becoming one of the hot research fields. Here, the development of TEGs including materials optimization, structural designs, and potential applications, even the opportunities, challenges, and the future development direction, is analyzed and summarized. Materials optimization and structural designs of flexibility for potential applications in wearable electronics are systematically discussed. With the development of flexible and wearable electronic equipment, flexible TEGs show increasingly great application prospects in artificial intelligence, self-powered sensing systems, and other fields in the future.
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In order to effectively synthesize chiral α-amino aldehydes, which have a wide range of potential applications in organic synthesis and medicinal chemistry, a highly chemo- and enantioselective hydrogenation of α-formyl enamides has been developed, catalyzed by a rhodium complex of a P-stereogenic bisphosphine ligand. Under different hydrogen pressures, the chiral α-amido aldehydes and ß-amido alcohols were obtained in high yields (97-99 %) and with excellent chemo- and enantioselectivities (up to >99.9 %â ee). The hydrogenation can be carried out on a gram scale and with a high substrate/catalyst ratio (up to 20 000 S/C), and the hydrogenated products were further converted into several important chiral products. Computations of the catalytic cycle gave a clear description for the R/S pathways, provided a reasonable explanation for the enantioselectivity, and revealed several other specific features.
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The first and collective total syntheses of periconiasinsâ A-E, a group of naturally occurring cytochalasans, were achieved by a series of rationally designed or bioinspired transformations. Salient features of the syntheses include a tandem aldol condensation/Grob fragmentation to assemble the linear polyketide-amino acid hybrid precursor, a Diels-Alder macrocylization to construct the 9/6/5 tricyclic core of periconiasinsâ A-C, and a transannular carbonyl-ene reaction to forge the polycyclic framework of periconiasinsâ D and E.
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Rhodium(II)-catalyzed intramolecular [4 + 3] cycloadditions of dienyltriazoles have been developed, which enable the efficient synthesis of various fused 2,5-dihydroazepines. Mechanistically, the titled reaction proceeds via an interesting tandem cyclopropanation/aza-cope rearrangement.
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Azepinas/química , Reação de Cicloadição , Ródio/química , Triazóis/química , Catálise , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Espectrometria de MassasRESUMO
Yolk-shell Si@void@C nanocomposites are prepared via a facile method of resorcinol-formaldehyde coating and LiOH etching, without SiO2 pre-modification on Si particles, expensive carbon sources, or environmentally-unfriendly HF solutions. Profiting from these favorable features, Si@void@C nanocomposites exhibit considerable reversible capacities (628 mA h g(-1) after 100 cycles) and good rate performances.
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The first rhodium(II)-catalyzed aza-[4+3] cycloadditions of 1-sulfonyl 1,2,3-triazoles with 1,3-dienes have been developed, and enable the efficient synthesis of highly functionalized 2,5-dihydroazepines from readily available precursors. In some cases, the reaction pathway could divert to formal aza-[3+2] cycloadditions, thus leading to 2,3-dihydropyrroles. In this context, the titled reaction represents a capable tool for the divergent synthesis of two types of synthetically valuable aza-heterocycles from common rhodium(II) iminocarbene intermediates.
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Alcadienos/química , Compostos Heterocíclicos/química , Ródio/química , Triazóis/química , Azepinas/química , Catálise , Reação de Cicloadição , Metano/análogos & derivados , Metano/química , Nitrogênio/químicaRESUMO
BACKGROUND: Ripeness is a phenotype that significantly impacts the quality of fruits, constituting a crucial factor in the cultivation and harvesting processes. Manual detection methods and experimental analysis, however, are inefficient and costly. RESULTS: In this study, we propose a lightweight and efficient melon ripeness detection method, MRD-YOLO, based on an improved object detection algorithm. The method combines a lightweight backbone network, MobileNetV3, a design paradigm Slim-neck, and a Coordinate Attention mechanism. Additionally, we have created a large-scale melon dataset sourced from a greenhouse based on ripeness. This dataset contains common complexities encountered in the field environment, such as occlusions, overlapping, and varying light intensities. MRD-YOLO achieves a mean Average Precision of 97.4% on this dataset, achieving accurate and reliable melon ripeness detection. Moreover, the method demands only 4.8 G FLOPs and 2.06 M parameters, representing 58.5% and 68.4% of the baseline YOLOv8n model, respectively. It comprehensively outperforms existing methods in terms of balanced accuracy and computational efficiency. Furthermore, it maintains real-time inference capability in GPU environments and demonstrates exceptional inference speed in CPU environments. The lightweight design of MRD-YOLO is anticipated to be deployed in various resource constrained mobile and edge devices, such as picking robots. Particularly noteworthy is its performance when tested on two melon datasets obtained from the Roboflow platform, achieving a mean Average Precision of 85.9%. This underscores its excellent generalization ability on untrained data. CONCLUSIONS: This study presents an efficient method for melon ripeness detection, and the dataset utilized in this study, alongside the detection method, will provide a valuable reference for ripeness detection across various types of fruits.