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1.
Nature ; 632(8027): 1032-1037, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39198671

RESUMO

Superconductivity in a highly correlated kagome system has been theoretically proposed for years (refs. 1-5), yet the experimental realization is hard to achieve6,7. The recently discovered vanadium-based kagome materials8, which exhibit both superconductivity9-11 and charge-density-wave orders12-14, are nonmagnetic8,9 and weakly correlated15,16. Thus these materials are unlikely to host the exotic superconductivity theoretically proposed. Here we report the discovery of a chromium-based kagome metal, CsCr3Sb5, which is contrastingly featured with strong electron correlations, frustrated magnetism and characteristic flat bands close to the Fermi level. Under ambient pressure, this kagome metal undergoes a concurrent structural and magnetic phase transition at 55 K, with a stripe-like 4a0 structural modulation. At high pressure, the phase transition evolves into two transitions, possibly associated with charge-density-wave and antiferromagnetic spin-density-wave orderings. These density-wave-like orders are gradually suppressed with pressure and, remarkably, a superconducting dome emerges at 3.65-8.0 GPa. The maximum of the superconducting transition temperature, Tcmax = 6.4 K, appears when the density-wave-like orders are completely suppressed at 4.2 GPa, and the normal state exhibits a non-Fermi-liquid behaviour, reminiscent of unconventional superconductivity and quantum criticality in iron-based superconductors17,18. Our work offers an unprecedented platform for investigating superconductivity in correlated kagome systems.

2.
EMBO J ; 43(8): 1519-1544, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38528180

RESUMO

Pericytes and endothelial cells (ECs) constitute the fundamental components of blood vessels. While the role of ECs in tumor angiogenesis and the tumor microenvironment is well appreciated, pericyte function in tumors remains underexplored. In this study, we used pericyte-specific deletion of the nitric oxide (NO) receptor, soluble guanylate cyclase (sGC), to investigate via single-cell RNA sequencing how pericytes influence the vascular niche and the tumor microenvironment. Our findings demonstrate that pericyte sGC deletion disrupts EC-pericyte interactions, impairing Notch-mediated intercellular communication and triggering extensive transcriptomic reprogramming in both pericytes and ECs. These changes further extended their influence to neighboring cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) through paracrine signaling, collectively suppressing tumor growth. Inhibition of pericyte sGC has minimal impact on quiescent vessels but significantly increases the vulnerability of angiogenic tumor vessels to conventional anti-angiogenic therapy. In conclusion, our findings elucidate the role of pericytes in shaping the tumor vascular niche and tumor microenvironment and support pericyte sGC targeting as a promising strategy for improving anti-angiogenic therapy for cancer treatment.


Assuntos
Neoplasias , Pericitos , Humanos , Pericitos/patologia , Pericitos/fisiologia , Guanilil Ciclase Solúvel , Células Endoteliais/fisiologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias/genética , Neoplasias/patologia , Guanilato Ciclase , Microambiente Tumoral
3.
Plant Cell ; 35(11): 4173-4189, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37506254

RESUMO

Drought, which can induce osmotic stress, is the leading environmental constraint on crop productivity. Plants in both agricultural and natural settings have developed various mechanisms to cope with drought stress. The identification of genes associated with drought stress tolerance and understanding the underlying regulatory mechanisms are prerequisites for developing molecular manipulation strategies to address this issue. Here, we reported that the G-BOX FACTOR 14-3-3f (14-3-3 protein OsGF14f) positively modulates osmotic stress tolerance in rice (Oryza sativa). OsGF14f transgenic lines had no obvious change in crucial agronomic traits including yield and plant height. OsGF14f is transcriptionally induced by PEG treatment, and in rice, overexpression or knockout of this gene leads to enhanced or weakened osmotic stress tolerance, respectively. Furthermore, OsGF14f positively regulates abscisic acid (ABA) responses by interacting with the core ABA-responsive transcription factor BASIC LEUCINE ZIPPER 23 (OsbZIP23) to enhance its transcriptional regulation activity toward downstream target genes. Further genetic analysis showed that OsGF14f is required for the full function of OsbZIP23 in rice osmotic response, and OsGF14f-mediated osmotic stress tolerance partially depends on OsbZIP23. Interestingly, OsGF14f is a direct target gene of OsbZIP23. Taken together, our findings reveal a genetic and molecular framework by which the OsGF14f-OsbZIP23 complex modulates rice osmotic response, providing targets for developing drought-tolerant crops.


Assuntos
Oryza , Oryza/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Estresse Fisiológico/genética , Pressão Osmótica , Proteínas de Plantas/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo
4.
Development ; 149(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36515165

RESUMO

Flowering time is an important agronomic trait affecting crop yield. FCS-LIKE ZINC FINGER (FLZ) proteins are plant-specific regulatory proteins that are involved in multiple biological processes. However, their roles in plant flowering time control have not been clarified. Here, we report that OsFLZ2 is a negative regulator of rice flowering time. OsFLZ2 delays flowering by repressing the expression of key floral integrator genes. Biochemical assays showed OsFLZ2 physically interacts with OsMADS51, a flowering activator under short-day (SD) conditions. Both OsFLZ2 and OsMADS51 are highly expressed in rice leaves before floral transition under natural SD conditions, and their proteins are colocalized in the nucleus. Co-expression of OsFLZ2 can destabilize OsMADS51 and weaken its transcriptional activation of the downstream target gene Early heading date 1 (Ehd1). Taken together, these results indicate that OsFLZ2 can interfere with the function of OsMADS51 to fine-tune rice flowering time.


Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
J Neurochem ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092633

RESUMO

Orexin is exclusively produced in neurons localized within the lateral hypothalamic area (LHA) and perifornical area (PFA). Orexin has been identified as a key promotor of arousal. The selective loss of orexinergic neurons results in narcolepsy. It is known that the intrinsic electrophysiological properties are critical for neurons to perform their functions in corresponding brain regions. In addition to hypothalamic orexin, other brain nuclei are involved in the regulation of sleep and wakefulness. Quite a lot of studies focus on elucidating orexin-induced regulation of sleep-wake states and modulation of neuronal electrophysiological properties in several brain regions. Here, we summarize that the orexinergic neurons exhibit spontaneous firing activity which is associated with the states of sleep-wake cycle. Orexin mainly exerts postsynaptic excitatory effects on multiple brain nuclei associated with the process of sleep and wakefulness. This review may provide a background to guide future research about the cellular mechanisms of orexin-induced maintaining of arousal.

6.
Small ; 20(31): e2311675, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38441359

RESUMO

The high oxygen electrocatalytic overpotential of flexible cathodes due to sluggish reaction kinetics result in low energy conversion efficiency of wearable zinc-air batteries (ZABs). Herein, lignin, as a 3D flexible carbon-rich macromolecule, is employed for partial replacement of polyacrylonitrile and constructing flexible freestanding air electrodes (FFAEs) with large amount of mesopores and multi-hollow channels via electrospinning combined with annealing strategy. The presence of lignin with disordered structure decreases the graphitization of carbon fibers, increases the structural defects, and optimizes the pore structure, facilitating the enhancement of electron-transfer kinetics. This unique structure effectively improves the accessibility of graphitic-N/pyridinic-N with oxygen reduction reaction (ORR) activity and pyridinic-N with oxygen evolution reaction (OER) activity for FFAEs, accelerating the mass transfer process of oxygen-active species. The resulting N-doped hollow carbon fiber films (NHCFs) exhibit superior bifunctional ORR/OER performance with a low potential difference of only 0.60 V. The rechargeable ZABs with NHCFs as metal-free cathodes possess a long-term cycling stability. Furthermore, the NHCFs can be used as FFAEs for flexible ZABs which have a high specific capacity and good cycling stability under different bending states. This work paves the way to design and produce highly active metal-free bifunctional FFAEs for electrochemical energy devices.

7.
Langmuir ; 40(1): 915-926, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38154048

RESUMO

High-efficiency dye desalination is crucial in the textile industry, considering its importance for human health, safe aquatic ecological systems, and resource recovery. In order to solve the problem of effective separation of univalent salt and ionic dye under the condition of high salt, ionic hyperbranched poly(amido-amine) (HBPs) were synthesized based on a simple and scalable one-step polycondensation method and then incorporated into the polyamide (PA) selective layers to construct charged nanochannels through interfacial polymerization (IP) on the surface of a polyvinyl chloride ultrafiltration (PVC-UF) hollow fiber membrane. Both the internal nanopores of HBPs (internal nanochannels) and the interfacial voids between HBPs and the PA matrix (external nanochannels) can be regarded as a fast water molecule transport pathway, while the terminal ionic groups of ionic HBPs endow the nanochannels with charge characteristics for improving ionic dye/salt selectivities. The permeate fluxes and dye/salt selectivities of HBP-TAC/PIP (57.3 L m-2 h-1 and rhodamine B (RB)/NaCl selectivity of 224.0) and HBP-PS/PIP (63.7 L m-2 h-1 and lemon yellow (LY)/NaCl selectivity of 664.0) membranes under 0.4 MPa operation pressure are much higher than PIP-only and HBP-NH2/PIP membranes. At the same time, this project also studied the membrane desalination process in a simulated high-salinity dye/salt mixture system to provide a theoretical basis and technical support for the actual dye desalination process.

8.
Biomacromolecules ; 25(2): 614-625, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38241010

RESUMO

Conductive hydrogels integrate the conductive performance and soft nature, which is like that of human skin. Thus, they are more suitable for the preparation of wearable human-motion sensors. Nevertheless, the integration of outstanding multiple functionalities, such as stretchability, toughness, biocompatibility, self-healing, adhesion, strain sensitivity, and durability, by a simple way is still a huge challenge. Herein, we have developed a multifunctional chitosan/oxidized hyaluronic acid/hydroxypropyl methylcellulose/poly(acrylic acid)/tannic acid/Al3+ hydrogel (CS/OHA/HPMC/PAA/TA/Al3+) by using a two-step method with hydroxypropyl methylcellulose (HPMC), acrylic acid (AA), tannic acid (TA), chitosan (CS), oxidized hyaluronic acid (OHA), and aluminum chloride hexahydrate (AlCl3·6H2O). Due to the synergistic effect of dynamic imine bonds between CS and OHA, dynamic metal coordination bonds between Al3+ and -COOH and/or TA as well as reversible hydrogen, the hydrogel showed excellent tensile property (elongation at break of 3168%) and desirable toughness (0.79 MJ/m3). The mechanical self-healing efficiency can reach 95.5% at 30 min, and the conductivity can recover in 5.2 s at room temperature without stimulation. The favorable attribute of high transparency (98.5% transmittance) facilitates the transmission of the optical signal and enables visualization of the sensor. It also shows good adhesiveness to various materials and is easy to peel off without residue. The resistance of the hydrogel-based sensors shows good electrical conductivity (2.33 S m-1), good durability, high sensing sensitivity (GF value of 4.12 under 1600% strain), low detection limit (less than 1%), and short response/recovery time (0.54/0.31 s). It adhered to human skin and monitored human movements such as the bending movements of joints, swallowing, and speaking successfully. Therefore, the obtained multifunctional conductive hydrogel has great potential applications in wearable strain sensors.


Assuntos
Quitosana , Polifenóis , Dispositivos Eletrônicos Vestíveis , Humanos , Adesivos , Ácido Hialurônico , Derivados da Hipromelose , Cimentos de Resina , Condutividade Elétrica , Hidrogéis , Íons
9.
Org Biomol Chem ; 22(23): 4656-4661, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38804023

RESUMO

The intermolecular [4 + 2] cycloaddition of o-hydroxy benzyl alcohols with isochroman ketals was realized by CF3CO2H catalysis. A broad range of bisbenzannulated [6,6]-spiroketals were formed under the metal-free mild conditions in moderate to excellent yields (45-98%) with mostly excellent diastereoselectivities (up to >20 : 1 dr). Furthermore, the enantioselective version was also preliminarily investigated and the bisbenzannulated [6,6]-spiroketal was obtained with 61% ee in the presence of Sc(OTf)3/Feng's chiral N,N'-dioxide ligand. Some of the bisbenzannulated [6,6]-spiroketal products showed good in vitro antifungal activities against Sclerotinia sclerotiorum and Rhizoctonia solani.

10.
Anal Bioanal Chem ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39190145

RESUMO

In this study, a ratiometric fluorescent sensor CdTe QDs@ZIF-8 with butterfly spectra is successfully constructed by in situ encapsulating mercaptopropionic acid-modified CdTe quantum dots in zeolitic imidazolate framework-8 (ZIF-8) with a simple strategy, and used for the detection of tetracycline in fluorescence/smartphone colorimetry dual-mode. ZIF-8 not only reduces the agglomeration of the quantum dots but also surprisingly generates a new green fluorescence signal at 524 nm while the red fluorescence of the CdTe quantum dots at 650 nm quenches when tetracycline is added. The two opposing fluorescence signals create a butterfly-shaped fluorescence spectrum, allowing the sensor to detect tetracycline over a linear range of 0-70 µM with the detection limit (LOD) of 0.0155 µM by using a ratiometric fluorescence technique. What is more, based on the obvious color change of the fluorescent sensor gradually from red to green under UV light, a highly stable point-of-care testing sensor has been developed for on-site detection of tetracycline through color recognition by smartphones, which can be used for real-time detection of this antibiotic in the range of 0-1000 µM with the LOD of 0.0249 µM. This work provides a simple and efficient method for the on-site detection of tetracycline.

11.
BMC Anesthesiol ; 24(1): 77, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408913

RESUMO

BACKGROUND: Extensive metastatic and refractory cancer pain is common, and exhibits a dissatisfactory response to the conventional intrathecal infusion of opioid analgesics. CASE PRESENTATION: The present study reports a case of an extensive metastatic esophageal cancer patient with severe intractable pain, who underwent translumbar subarachnoid puncture with intrathecal catheterization to the prepontine cistern. After continuous infusion of low-dose morphine, the pain was well-controlled with a decrease in the numeric rating scale (NRS) of pain score from 9 to 0, and the few adverse reactions to the treatment disappeared at a low dose of morphine. CONCLUSIONS: The patient achieved a good quality of life during the one-month follow-up period.


Assuntos
Dor do Câncer , Neoplasias , Dor Intratável , Humanos , Morfina , Dor Intratável/etiologia , Dor Intratável/induzido quimicamente , Dor do Câncer/tratamento farmacológico , Qualidade de Vida , Analgésicos Opioides , Injeções Espinhais/efeitos adversos
12.
Pestic Biochem Physiol ; 203: 106015, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39084806

RESUMO

Beauveria bassiana is a popular and eco-friendly biopesticide. During its pathogen-pest interaction, both N-acetylglucosamine (GlcNAc) catabolism and anabolism are crucial for nutrient supply and cell-wall construction. The initiation of GlcNAc metabolism relies on the catalysis of GlcNAc kinase, which has been extensively studied in the human pathogen Candida albicans. However, the physiological function of GlcNAc kinase remains poorly understood in entomopathogenic fungi. In the present study, a GlcNAc kinase homolog was identified and designated as BbHxk1 in B. bassiana. Deletion of BbHxk1 resulted in viable but reduced vegetative growth on various carbon sources. ΔBbHxk1 mutants displayed severe defects in cell wall integrity, making them more susceptible to cell wall stress cues. Furthermore, the absence of BbHxk1 resulted in an increase in conidial yield and blastospore production, and a faster rate of germination and filamentation, potentially attributed to higher intracellular ATP levels. BbHxk1 deficiency led to a reduction in the activities of cuticle-degrading enzymes, which might contribute to the attenuated pathogenicity specifically through cuticle penetration rather than hemocoel infection towards Galleria mellonella larvae. Being different from C. albicans Hxk1, which facultatively acts as a catalyzing enzyme and transcriptional regulator, BbHxk1 primarily acts as a catalyzing enzyme and metabolic regulator. The altered metabolomic profiling correlated with the phenotypic defects in ΔBbHxk1 mutants, further implicating a potential metabolism-dependent mechanism of BbHxk1 in mediating physiologies of B. bassiana. These findings not only unveil a novel role for GlcNAc kinase in B. bassiana, but also provide a solid theoretical basis to guide metabolic reprogramming in order to maintain or even enhance the efficiency of fungi for practical applications.


Assuntos
Beauveria , Parede Celular , Fosfotransferases (Aceptor do Grupo Álcool) , Beauveria/patogenicidade , Beauveria/genética , Parede Celular/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Animais , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Esporos Fúngicos , Mariposas/microbiologia , Agentes de Controle Biológico
13.
Mikrochim Acta ; 191(7): 432, 2024 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951266

RESUMO

Cystinuria is a genetic disorder, and in severe cases, it might lead to kidney failure. As an important biomarker for cystinuria, the level of arginine (Arg) in urine is a vital indicator for cystinuria screening. Therefore, it is urgently needed to detect Arg with high selectivity and sensitivity. In this work, a boric acid functionalized Zr-based metal-organic framework UiO-PhbA is prepared by grafting phenylboronic acid on UiO-66-NH2 through a Schiff base reaction using a covalent post-synthesis modification (CPSM) strategy. The prepared UiO-PhbA exhibits a sensitive and specific fluorescence "turn-on" response to Arg and can be exploited to detect Arg in human serum and urine samples with a broad linear range of 0.6-350 µM and low limit of detection (LOD) of 18.45 nM. This study provides a new and reliable rapid screening protocol for sulfite oxidase deficiency-related diseases.


Assuntos
Arginina , Biomarcadores , Ácidos Borônicos , Cistinúria , Corantes Fluorescentes , Limite de Detecção , Estruturas Metalorgânicas , Humanos , Cistinúria/diagnóstico , Cistinúria/urina , Estruturas Metalorgânicas/química , Corantes Fluorescentes/química , Arginina/química , Arginina/sangue , Biomarcadores/urina , Biomarcadores/sangue , Ácidos Borônicos/química , Espectrometria de Fluorescência/métodos , Zircônio/química
14.
Aesthetic Plast Surg ; 48(12): 2231-2238, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38528128

RESUMO

BACKGROUND:  Infraorbital filler injection is a commonly used minimally invasive cosmetic procedure on the face, which can cause vascular complications. OBJECTIVE:  In this study, we aimed to explore the anatomical structure of the infraorbital vasculature and to establish an accurate protocol for infraorbital filler injection. METHODS:  The vascular structure of the infraorbital region was evaluated in 84 hemifacial specimens using computed tomography. Four segments (P1-P4) and five sections (C1-C5) were considered. We recorded the number of identified arteries in each slice and at each location and the number of deep arteries. Furthermore, we also measured the infraorbital artery (IOA) distribution. RESULTS:  At P1-P4, the lowest number of arteries was detected in segment P4, with a 317/1727 (18.4%) and 65/338 (2.3%) probability of total and deep arterial identification, respectively. The probabilities of encountering an identified artery at the five designated locations (C1-C5) were 277/1727 (16%), 318/1727 (18.4%), 410/1727 (23.7%), 397/1727 (23%), and 325/1727 (18.8%), respectively. The probability of an IOA being identified at C2 was 68/84 (81%). CONCLUSION:  We described an effective filler injection technique in the infraorbital region to minimize the associated risks. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Preenchedores Dérmicos , Órbita , Humanos , Feminino , Masculino , Preenchedores Dérmicos/efeitos adversos , Preenchedores Dérmicos/administração & dosagem , Órbita/irrigação sanguínea , Técnicas Cosméticas/efeitos adversos , Cadáver , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Idoso , Face/irrigação sanguínea , Idoso de 80 Anos ou mais
15.
BMC Genomics ; 24(1): 504, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37649000

RESUMO

BACKGROUND: Laccases are green biocatalysts with wide industrial applications. The study of efficient and specific laccase producers remains a priority. Cerrena species have been shown to be promising basidiomycete candidates for laccase production. Although two sets of Cerrena genome data have been publicly published, no comprehensive bioinformatics study of laccase gene family in C. unicolor has been reported, particularly concerning the analysis of their three-dimensional (3D) structures and molecular docking to substrates, like ABTS and aflatoxin B1 (AFB1). RESULTS: In this study, we conducted a comprehensive genome-wide analysis of laccase gene family in C. unicolor 87613. We identified eighteen laccase genes (CuLacs) and classified them into three clades using phylogenetic analysis. We characterized these laccases, including their location in contig 5,6,9,12,15,19,26,27, gene structures of different exon-intron arrangements, molecular weight ranging from 47.89 to 141.41 kDa, acidic pI value, 5-15 conserved protein motifs, signaling peptide of extracellular secretion (harbored by 13 CuLacs) and others. In addition, the analysis of cis-acting element in laccase promoters indicated that the transcription response of CuLac gene family was regulatable and complex under different environmental cues. Furthermore, analysis of transcription pattern revealed that CuLac8, 12 and CuLac2, 13 were the predominant laccases in response to copper ions or oxidative stress, respectively. Finally, we focused on the 3D structure analysis of CuLac proteins. Seven laccases with extra transmembrane domains or special sequences were particularly interesting. Predicted structures of each CuLac protein with or without these extra sequences showed altered interacting amino acid residues and binding sites, leading to varied affinities to both ABTS and AFB1. As far as we know, it is the first time to discuss the influence of the extra sequence on laccase's affinity to substrates. CONCLUSIONS: Our findings provide robust genetic data for a better understanding of the laccase gene family in C. unicolor 87613, and create a foundation for the molecular redesign of CuLac proteins to enhance their industrial applications.


Assuntos
Estudo de Associação Genômica Ampla , Lacase , Lacase/genética , Simulação de Acoplamento Molecular , Filogenia
16.
J Am Chem Soc ; 145(11): 6535-6545, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36912664

RESUMO

Transition-metal-catalyzed enantioselective functionalization of acyl radicals has so far not been realized, probably due to their relatively high reactivity, which renders the chemo- and stereocontrol challenging. Herein, we describe Cu(I)-catalyzed enantioselective desymmetrizing C-O bond coupling of acyl radicals. This reaction is compatible with (hetero)aryl and alkyl aldehydes and, more importantly, displays a very broad scope of challenging alcohol substrates, such as 2,2-disubstituted 1,3-diols, 2-substituted-2-chloro-1,3-diols, 2-substituted 1,2,3-triols, 2-substituted serinols, and meso primary 1,4-diols, providing enantioenriched esters characterized by challenging acyclic tetrasubstituted carbon stereocenters. Partnered by one- or two-step follow-up transformations, this reaction provides a convenient and practical strategy for the rapid preparation of chiral C3 building blocks from readily available alcohols, particularly the industrially relevant glycerol. Mechanistic studies supported the proposed C-O bond coupling of acyl radicals.

17.
Small ; 19(48): e2303864, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37525330

RESUMO

Silicon (Si) is regarded as one of the most promising anode materials for high-performance lithium-ion batteries (LIBs). However, how to mitigate its poor intrinsic conductivity and the lithiation/delithiation-induced large volume change and thus structural degradation of Si electrodes without compromising their energy density is critical for the practical application of Si in LIBs. Herein, an integration strategy is proposed for preparing a compact micron-sized Si@G/CNF@NC composite with a tight binding and dual-encapsulated architecture that can endow it with superior electrical conductivity and deformation resistance, contributing to excellent cycling stability and good rate performance in thick electrode. At an ultrahigh mass loading of 10.8 mg cm-2 , the Si@G/CNF@NC electrode also presents a large initial areal capacity of 16.7 mA h cm-2 (volumetric capacity of 2197.7 mA h cm-3 ). When paired with LiNi0.95 Co0.02 Mn0.03 O2 , the pouch-type full battery displays a highly competitive gravimetric (volumetric) energy density of ≈459.1 Wh kg-1 (≈1235.4 Wh L-1 ).

18.
Anal Biochem ; 667: 115087, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36858251

RESUMO

Reduced graphene oxide-gold nanoparticles nanocomposites (rGO-AuNPs) with high surface-enhanced Raman scattering (SERS) activity was created by biomass-assisted green synthesis with Lilium casa blanca petals biomass for the first time, and its application for methylene blue (MB) degradation was explored through in-situ monitoring. Lilium casa blanca petals biomass was used as a reducing agent to reduce GO and chloroauric acid successively when carrying out rGO-AuNPs in-situ synthesis while it also acted as a capping agent. The produced rGO had oxygen-containing functional groups which had an outstanding performance in enhancing the SERS effect. Characterization results confirmed that the AuNPs were grafted onto the rGO sheet, and the mechanism study showed that total flavonoids in Lilium casa blanca petals biomass were the main biological compounds involved in the reduction. rGO-AuNPs had a high Raman enhancement factor (EF) which could reach 3.88 × 107. The synthesized nanocomposite also had a good catalytic activity that could be employed as catalyst in MB degradation, and it could complete degradation within 15min. The reaction rate increased linearly with the amount of rGO-AuNPs, and the degradation could be in-situ monitored both by UV and SERS.


Assuntos
Grafite , Nanopartículas Metálicas , Ouro/química , Nanopartículas Metálicas/química , Azul de Metileno , Análise Espectral Raman/métodos , Biomassa , Grafite/química
19.
Theor Appl Genet ; 136(12): 251, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985474

RESUMO

KEY MESSAGE: Genome-wide association mapping revealed a novel QTL for shoot length across multiple environments. Its causal gene, LOC_Os01g68500, was identified firstly through gene-based haplotype analysis, gene expression and knockout transgenic verification. Strong seedling vigor is an important breeding target for rice varieties used in direct seeding. Shoot length (SL) is one of the important traits associated with seedling vigor characterized by rapid growth of seedling, which enhance seedling emergence. Therefore, mining genes for SL and conducting molecular breeding help to develop varieties for direct seeding. However, few QTLs for SL have been fine mapped or cloned so far. In this study, a genome-wide association study of SL was performed in a diverse rice collection consisting of 391 accessions in two years, using phenotypes generated by different cultivation methods according to the production practice, and a total of twenty-four QTLs for SL were identified. Among them, the novel QTL qSL-1f on chromosome 1 could be stably detected across all three cultivation methods in the whole population and indica subpopulation. Through gene-based haplotype analysis of the annotated genes within the putative region of qSL-1f, and validated by gene expression and knockout transgenic experiments, LOC_Os01g68500 (i.e., Os01g0913100 in RAP-DB) was identified as the causal gene for SL, which has a single-base variation (C-to-A transversion) in its CDS region, resulting in the significant difference in SL of rice. LOC_Os01g68500 encodes a DUF538 (Domain of unknown function) containing protein, and the function of DUF538 protein gene on rice seedling growth is firstly reported in this study. These results provide a new clue for exploring the molecular mechanism regulating SL, and promising gene source for the molecular breeding in rice.


Assuntos
Oryza , Oryza/genética , Estudo de Associação Genômica Ampla , Haplótipos , Melhoramento Vegetal , Mapeamento Cromossômico/métodos , Plântula/genética
20.
Virol J ; 20(1): 24, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755309

RESUMO

BACKGROUND: Infection following lung transplantation has been the focus of clinical concerns. The colonization rate of commensal bacteria of the urogenital tract, including Mycoplasma hominis, Ureaplasma urealyticum (UU), and herpes simplex virus type-2 (HSV-2), is high, which may cause secondary infection after transplantation. CASE PRESENTATION: Twenty-three-year-old and 67-year-old women underwent lung transplantation for different causes. Shortly after the operation, they developed perineal skin ulcers, hypoxia, and intractable epilepsy. Subsequent computed tomography (CT) of the chest showed lung consolidation, and cranial CT showed shallowing sulci and gyri. UU and HSV-2 were detected in bronchoalveolar lavage fluid by next-generation sequencing, and HSV-2 was shown in the cerebrospinal fluid of both patients. Despite active treatment, both suffered irreversible brain function damage within 72 h of the seizure. CONCLUSIONS: Clinicians should know that commensal bacteria of urogenital tract infections can lead to fatal multiple organ dysfunction after lung transplantation.


Assuntos
Infecções por Mycoplasma , Humanos , Adulto , Feminino , Adulto Jovem , Infecções por Mycoplasma/complicações , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/microbiologia , Transplantados , Insuficiência de Múltiplos Órgãos , Ureaplasma urealyticum , Bactérias , Pulmão/diagnóstico por imagem
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