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1.
Sci Adv ; 10(4): eadd9485, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38266097

RESUMO

Type IV pili (TFP) are known to be functionally related to cell motilities and natural transformation in many bacteria. However, the molecular and ecological functions of the TFP have rarely been reported for photosynthetic cyanobacteria. Here, by labeling pili in model cyanobacterium Synechococcus elongatus PCC 7942 (Syn7942), we have quantitatively characterized the TFP and its driven twitching motility in situ at the single-cell level. We found an oscillating pattern of TFP in accordance with the light and dark periods during light-dark cycles, which is correlated positively to the oscillating pattern of the natural transformation efficiency. We further showed that the internal circadian clock plays an important role in regulating the oscillating pattern of TFP, which is also supported by evidences at the molecular level by tracking the expression of 16 TFP-related genes. This study adds a detailed picture toward the gap between TFP and its relations to circadian regulations in Syn7942.


Assuntos
Relógios Circadianos , Synechococcus , Synechococcus/genética , Fímbrias Bacterianas , Cabelo
2.
Small ; : e2307377, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940628

RESUMO

P2-Na2/3 Ni1/3 Mn2/3 O2 cathode materials have garnered significant attention due to their high cationic and anionic redox capacity under high voltage. However, the challenge of structural instability caused by lattice oxygen evolution and P2-O2 phase transition during deep charging persists. A breakthrough is achieved through a simple one-step synthesis of Cr, Mg co-doped P2-NaNMCM, resulting in a bi-functional improvement effect. P2-NaNMCM-0.01 exhibits an impressive capacity retention rate of 82% after 100 cycles at 1 C. In situ X-ray diffraction analysis shows that the "pillar effect" of Mg mitigates the weakening of the electrostatic shielding and effectively suppresses the phase transition of P2-O2 during the charging and discharging process. This successfully averts serious volume expansion linked to the phase transition, as well as enhances the Na+ migration. Simultaneously, in situ Raman spectroscopy and ex situ X-ray photoelectron spectroscopy tests demonstrate that the strong oxygen affinity of Cr forms a robust TM─O bond, effectively restraining lattice oxygen evolution during deep charging. This study pioneers a novel approach to designing and optimizing layered oxide cathode materials for sodium-ion batteries, promising high operating voltage and energy density.

3.
Eur J Clin Nutr ; 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978257

RESUMO

BACKGROUND/OBJECTIVES: Relationship between dietary intake and sensory sensitivity and intelligence in autism spectrum disorder (ASD) is not well described. This study aims to investigate nutrition status in children with ASD and ID and its association with sensory sensitivity and intelligence. SUBJECTS/METHODS: 84 students (34 ASD and 48 ID) in a special education school were recruited. Dietary intakes were evaluated with 3-day food dairy. Sensory sensitivity was measured using short sensory profile (SSP). Wechsler IQ test were performed. RESULTS: Two out of twenty-four investigated nutrients had an adequate intake rate of over 50%. Four out of ten investigated vitamins had an inadequate intake rate of over 90% and another two over 80%. 75.6% of participants had inadequate energy intake. After adjusting for age, ASD participants had a higher intake of all surveyed nutrients but only the intake of vitamin E and folate were statistically different (p < 0.05) along with a smaller number of inadequate nutrients (p < 0.001). Taste/smell sensitivity, movement sensitivity, underresponsive/seeks sensation, and total sensory sensitivity symptoms severity were slightly higher in ASD group than in ID group (all p < 0.05). After adjusting for IQ and sensory sensitivity score, difference of number of inadequate nutrients between ASD and ID group were not statistically significant (p = 0.193). CONCLUSIONS: Individuals with ASD had better dietary intake but worse sensory sensitivity compared to those with ID. Sensory sensitivity and intelligence are correlated with nutritional status in individuals with neurodevelopmental disorder.

4.
Inorg Chem ; 62(46): 18809-18813, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37943673

RESUMO

The design of a highly and photomodulated proton conductor is important for advanced potential applications in chemical sensors and bioionic functions. In this work, a metal-organic framework (MOF; Gd-NO2) with high proton conductivity is synthesized with a photosensitive ligand of 5-nitroisophthalic acid (BDC-NO2), and it provides remote-control photomodulated proton-conducting behavior. The proton conduction of Gd-NO2 reaches 3.66 × 10-2 S cm-1 at 98% relative humidity (RH) and 25 °C, while it decreases by ∼400 times after irradiation with a 355 nm laser. The newly generated and disappearing FT-IR characteristic peaks reveal that this photomodulated process is realized by the photoinduced transformation from BDC-NO2 to 5-nitroso-isophthalic acid (BDC-NO). According to density functional theory, the smaller electronegativity of the -NO group, the longer distance of the hydrogen bond between BDC-NO and H2O molecules, and the lower water adsorption energy of BDC-NO indicate that the irradiated sample possesses a poorer hydrophilicity and has difficulty forming rich hydrogen-bonded networks, which results in the remarkable decrease of proton conductivity.

5.
Sheng Wu Gong Cheng Xue Bao ; 39(11): 4534-4549, 2023 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-38013182

RESUMO

As an important protein structure on the surface of bacteria, type Ⅳ pili (TFP) is the sensing and moving organ of bacteria. It plays a variety of roles in bacterial physiology, cell adhesion, host cell invasion, DNA uptake, protein secretion, biofilm formation, cell movement and electron transmission. With the rapid development of research methods, technical equipment and pili visualization tools, increasing number of studies have revealed various functions of pili in cellular activities, which greatly facilitated the microbial single cell research. This review focuses on the pili visualization method and its application in the functional research of TFP, providing ideas for the research and application of TFP in biology, medicine and ecology.


Assuntos
Proteínas de Bactérias , Fímbrias Bacterianas , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Proteínas de Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Aderência Bacteriana/fisiologia
6.
Dalton Trans ; 52(36): 12869-12877, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37622489

RESUMO

Aqueous rechargeable zinc ion batteries (ARZIBs) are ideal for massive and longstanding energy storage applications because of their excellent security and low operation cost. Nevertheless, ARZIBs are subject to the severe corrosion reaction of zinc metal anodes that is derived from the thermodynamic unsteadiness of the zinc anodes in aqueous solution, as well as zinc dendrite growth originating from uncontrolled zinc deposition. Herein, we created a separator by coating a thin piece of polypropylene (PP) with a compound consisting of zinc trifluoromethanesulfonate [Zn(OTf)2] and poly(vinylidene fluoride-hexafluoropropylene (PVDF-HFP). Consequently, the severe corrosion reaction of the zinc metal anodes and the profuse formation of zinc dendrites were effectively mitigated by the novel PP separator, which prolonged the lifetime of the zinc metal anodes. When a zinc metal plating layer was used with preferential (002) crystallographic orientation, the cyclic performance over 1100 h of the symmetrical Zn∥Zn battery based on the novel separator was steady. Additionally, the Zn∥MnO2 batteries exhibited an impressive specific capacity and competitive long durability of 75.5% over 500 cycles at a current density of 0.1 A g-1. With this work, we intend to set the standard for designing novel separators in the construction of advanced zinc anodes for high-performance ARZIBs.

7.
J Chem Phys ; 159(5)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37526163

RESUMO

DeePMD-kit is a powerful open-source software package that facilitates molecular dynamics simulations using machine learning potentials known as Deep Potential (DP) models. This package, which was released in 2017, has been widely used in the fields of physics, chemistry, biology, and material science for studying atomistic systems. The current version of DeePMD-kit offers numerous advanced features, such as DeepPot-SE, attention-based and hybrid descriptors, the ability to fit tensile properties, type embedding, model deviation, DP-range correction, DP long range, graphics processing unit support for customized operators, model compression, non-von Neumann molecular dynamics, and improved usability, including documentation, compiled binary packages, graphical user interfaces, and application programming interfaces. This article presents an overview of the current major version of the DeePMD-kit package, highlighting its features and technical details. Additionally, this article presents a comprehensive procedure for conducting molecular dynamics as a representative application, benchmarks the accuracy and efficiency of different models, and discusses ongoing developments.

8.
Cell Rep ; 42(7): 112748, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37405916

RESUMO

Pioneer transcription factors interact with nucleosomes to scan silent, compact chromatin, enabling cooperative events that modulate gene activity. While at a subset of sites pioneer factors access chromatin by assisted loading with other transcription factors, the nucleosome-binding properties of pioneer factors enable them to initiate zygotic genome activation, embryonic development, and cellular reprogramming. To better understand nucleosome targeting in vivo, we assess whether pioneer factors FoxA1 and Sox2 target stable or unstable nucleosomes and find that they target DNase-resistant, stable nucleosomes, whereas HNF4A, a non-nucleosome binding factor, targets open, DNase-sensitive chromatin. Despite FOXA1 and SOX2 targeting similar proportions of DNase-resistant chromatin, using single-molecule tracking, we find that FOXA1 uses lower nucleoplasmic diffusion and longer residence times while SOX2 uses higher nucleoplasmic diffusion and shorter residence times to scan compact chromatin, while HNF4 scans compact chromatin much less efficiently. Thus, pioneer factors target compact chromatin through distinct processes.


Assuntos
Cromatina , Fator 3-alfa Nuclear de Hepatócito , Nucleossomos , Fatores de Transcrição SOXB1 , Desoxirribonucleases/metabolismo , Ligação Proteica , Fatores de Transcrição/metabolismo , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Fatores de Transcrição SOXB1/metabolismo
9.
Nano Lett ; 23(6): 2277-2286, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36913627

RESUMO

Colloidal nanocrystals (NCs) have shown remarkable promise for optoelectronics, energy harvesting, photonics, and biomedical imaging. In addition to optimizing quantum confinement, the current challenge is to obtain a better understanding of the critical processing steps and their influence on the evolution of structural motifs. Computational simulations and electron microscopy presented in this work show that nanofaceting can occur during nanocrystal synthesis from a Pb-poor environment in a polar solvent. This could explain the curved interfaces and the olivelike-shaped NCs observed experimentally when these conditions are employed. Furthermore, the wettability of the PbS NCs solid film can be further modified via stoichiometry control, which impacts the interface band bending and, therefore, processes such as multiple junction deposition and interparticle epitaxial growth. Our results suggest that nanofaceting in NCs can become an inherent advantage when used to modulate band structures beyond what is traditionally possible in bulk crystals.

10.
Trends Biochem Sci ; 48(6): 513-526, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36990958

RESUMO

Heterochromatin is defined as a chromosomal domain harboring repressive H3K9me2/3 or H3K27me3 histone modifications and relevant factors that physically compact the chromatin. Heterochromatin can restrict where transcription factors bind, providing a barrier to gene activation and changes in cell identity. While heterochromatin thus helps maintain cell differentiation, it presents a barrier to overcome during efforts to reprogram cells for biomedical purposes. Recent findings have revealed complexity in the composition and regulation of heterochromatin, and shown that transiently disrupting the machinery of heterochromatin can enhance reprogramming. Here, we discuss how heterochromatin is established and maintained during development, and how our growing understanding of the mechanisms regulating H3K9me3 heterochromatin can be leveraged to improve our ability to direct changes in cell identity.


Assuntos
Heterocromatina , Histonas , Histonas/metabolismo , Cromatina , Diferenciação Celular , Fatores de Transcrição/metabolismo
11.
Org Lett ; 25(9): 1436-1440, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36856532

RESUMO

A mild strategy for Co(III)-catalyzed C(sp2)-H cyanation of indoles was developed by using NCBLD as an electrophilic cyanation reagent and 1-butyl-3-acetylimidazole ditrifluoromethylsulfonimide ([BAIM]NTf2) as an environmentally friendly and recyclable solvent, and a series of 2-cyano products were obtained at room temperature. Adopting this strategy, the unnatural nucleotide fragment precursor of Remdesivir, which was a drug for COVID-19, was synthesized through cyano transformation, further proving the practicability of this cyanation method.

12.
Chem Asian J ; 18(8): e202300039, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36815283

RESUMO

N-trifluoromethylsuccinimide (NTFS) as a new trifluoromethylation reagent was designed and prepared via Ag-CF3 , and applied to the direct trifluoromethylation of free aniline, and a series of trifluoromethyl products were obtained with good yields. The practicability of the protocol was verified by a gram-level experiment and the synthesis of the antiasthmatic drug Mabuterol. In addition, a possible radical mechanism was proposed and verified by related experiments. The protocol provided a new solution for C-H trifluoromethylation of free anilines.

13.
Adv Mater ; 35(2): e2208974, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36401825

RESUMO

The synthesis of cathode materials plays an important role in determining the production efficiency, cost, and performance of lithium-ion batteries. However, conventional synthesis methods always experience a slow heating rate and involve a complicated multistep reaction process and sluggish reaction dynamics, leading to high energy and long time consumption. Herein, a high-temperature shock (HTS) strategy is reported for the ultrafast synthesis of cathode materials in seconds. The HTS process experiences an ultrahigh heating rate, leading to a non-equilibrium reaction and fast reaction kinetics, and avoids high energy and long time consumption. Mainstream cathode materials (such as LiMn2 O4 , LiCoO2 , LiFePO4 , and Li-rich layered oxide/NiO heterostructured material) are successfully synthesized with pure phases, oxygen vacancies, ultrasmall particle sizes, and good electrochemical performance. The HTS process not only provides an efficient synthesis approach for cathode materials, but also can be extended beyond lithium-ion batteries.

14.
Cell Signal ; 101: 110518, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36351508

RESUMO

BACKGROUND: Acute myocardial infarction (MI) is considered to be the main cause of congestive heart failure. The aim of this study was to provide an in-depth analysis of athophysiological processes and provide key targets for intervention in the occurrence of acute MI. METHODS: A rat model of MI was established by ligation of left anterior descending branch. Heart tissue, epicardial adipose tissue (EAT) and subcutaneous adipose tissue (SAT) were collected. H9c2 cells were used to explore the mechanism of complement factor D (CFD) regulating cardiomyocyte apoptosis. RESULTS: Myocardial apoptosis were observed in MI rat, and more EAT was found in the MI group in vivo. The conditioned medium prepared by EAT (EAT-CM) significantly reduced the activity of H9c2 cells. The content of CFD in EAT was significantly increased, and CFD promoted cardiomyocyte apoptosis in vitro and CFD-IN1 (a selective inhibitor of CFD) could revised this effect. CFD induced poly ADP-ribosepolymerase-1 (PARP-1) overactivation. Furthermore, the addition of pan-caspase inhibitor Z-VAD in the SAT-CM + CFD group couldn't affect H9c2 cell apoptosis. CFD induced cell apoptosis via PARP-1 activation and PARP-1 inhibitor 3-Aminobenzamide could revise this effect. The injection of CFD-IN1 in MI rat model confirmed that inhibition of CFD activity alleviated cardiomyocytes apoptosis. CONCLUSION: Our findings indicate that EAT mediating cardiomyocyte apoptosis after MI through secretion of CFD and activation of PARP-1 activity.


Assuntos
Fator D do Complemento , Infarto do Miocárdio , Miócitos Cardíacos , Poli(ADP-Ribose) Polimerase-1 , Animais , Ratos , Tecido Adiposo , Apoptose , Fator D do Complemento/farmacologia , Poli(ADP-Ribose) Polimerase-1/metabolismo
15.
World J Gastrointest Endosc ; 15(12): 699-704, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38187914

RESUMO

BACKGROUND: Preoperative diagnosis of appendiceal mucinous neoplasms is challenging, and there are few reports regarding the endosonographic characteristics of these neoplasms. AIM: To provide a retrospective assessment of the imaging features of appendiceal mucinous neoplasms using endoscopic ultrasound (EUS) by curved linear-array echoendoscope. METHODS: A database of all patients with appendiceal mucinous neoplasms who had received EUS examination at our hospital between January 2018 and July 2023 was retrospectively analyzed. The EUS characteristics and patients' clinical data were reviewed. RESULTS: Twenty-two patients were included in the study. The linear-array echoendoscope successfully reached the ileocecal region in every patient. In the endoscopic view, we could observe the protrusion in the appendiceal orifice in all patients. A volcano sign was observed in two patients, and an atypical volcano sign was seen in two patients. EUS showed that all 22 lesions were submucosal cystic hypoechoic lesions with clear boundaries. No wall nodules were observed, but an onion-peeling sign was observed in 17 cases. CONCLUSION: Linear-array echoendoscope is safe to reach the ileocecal region under the guidance of EUS. Image features on endoscopic and echoendosonograhic views could be used to diagnose appendiceal mucinous neoplasms.

16.
Nanomaterials (Basel) ; 12(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080031

RESUMO

Electrochemical energy storage devices (EESDs) have caused widespread concern, ascribed to the increasing depletion of traditional fossil energy and environmental pollution. In recent years, nickel cobalt bimetallic sulfides have been regarded as the most attractive electrode materials for super-performance EESDs due to their relatively low cost and multiple electrochemical reaction sites. In this work, NiCo-bimetallic sulfide NixCo3-xS4 particles were synthesized in a mixed solvent system with different proportion of Ni and Co salts added. In order to improve the electrochemical performance of optimized Ni2.5Co0.5S4 electrode, the Ni2.5Co0.5S4 particles were annealed at 350 °C for 60 min (denoted as Ni2.5Co0.5S4-350), and the capacity and rate performance of Ni2.5Co0.5S4-350 was greatly improved. An aqueous NiCo-Zn battery was assembled by utilizing Ni2.5Co0.5S4-350 pressed onto Ni form as cathode and commercial Zn sheet as anode. The NiCo-Zn battery based on Ni2.5Co0.5S4-350 cathode electrode delivers a high specific capacity of 232 mAh g-1 at 1 A g-1 and satisfactory cycling performance (65% capacity retention after 1000 repeated cycles at 8 A g-1). The as-assembled NiCo-Zn battery deliver a high specific energy of 394.6 Wh kg-1 and long-term cycling ability. The results suggest that Ni2.5Co0.5S4-350 electrode has possible applications in the field of alkaline aqueous rechargeable electrochemical energy storage devices for supercapacitor and NiCo-Zn battery.

17.
Phys Chem Chem Phys ; 24(36): 21722-21728, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36082747

RESUMO

Recently, twisted bilayer graphene (TBLG) has attracted enormous attention owing to its peculiar electronic properties. In this work, the anisotropic thermal conductivity of TBLG is comprehensively investigated. It is reported that interlayer twisting can be a practical approach for thermal transport regulation with high accuracy. A strong non-monotonic correlation between anisotropic thermal conductivity and twisting angles is revealed. Extensive phonon behavior analyses reveal the physical mechanism. The anisotropic thermal transport in TBLG is explained by the calculated phonon density of states (PDOS). Meanwhile, the phonon spectra and phonon relaxation times extracted from spectral energy density (SED) profiles explain the decreasing trend of thermal conductivity with increasing twisting angles. The increase in thermal conductivity is attributed to the combined effects of twist and anisotropy. The reported anisotropic thermal conductivity is important to the thermal modulation and our analyses provide a valuable complement to the phonon studies of TBLG.

18.
Carbohydr Polym ; 296: 119952, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36088031

RESUMO

The gut cell wall is considered an impenetrable barrier to orally administrated polysaccharides. We recently reported a selective lymphatic route for Radix Astragali polysaccharide RAP to enter Peyer's patches (PPs) to trigger immune responses. However, how RAP enters PPs is unclear. Herein, we screened the intestinal epithelial cells of mice and found that the follicle-associated epithelium cells were specifically bound with FITC-RAP. Further studies in vitro and in vivo revealed that RAP was efficiently transported by microfold (M) cells. We also confirmed that M cell-transported RAP directly contacted dendritic cells. More importantly, for the first time, we verified this interesting M cell-mediated transcytosis of RAP in the human distal ileum. Mechanistically, we identified M cells to be the transporter cells that independently deliver RAP into the lymphatic system to trigger immune responses. This interesting transcytosis mechanism might apply to many other immunomodulatory polysaccharides orally dosed to human body.


Assuntos
Astrágalo , Nódulos Linfáticos Agregados , Células Epiteliais/metabolismo , Epitélio , Humanos , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia
19.
RSC Adv ; 12(32): 20447-20453, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35919191

RESUMO

Porous micro/nanostructure electrode materials have always contributed to outstanding electrochemical energy storage performances. Co9S8 is an ideal model electrode material with high theoretical specific capacity due to its intrinsic two crystallographic sites of cobalt ions. In order to improve the conductivity and specific capacitance of Co9S8, nickel ions were introduced to tune the electronic structure of Co9S8. The morphology design of the mesoporous hollow sphere structure guarantees cycle stability and ion diffusion. In this work, Ni x Co9-x S8 mesoporous hollow spheres were synthesized via a facile partial ion-exchange of Co9S8 mesoporous hollow spheres without using a template, boosting the capacitance to 1300 F g-1 at the current density of 1 A g-1. Compared with the pure Co9S8 and Ni-Co9S8-30%, Ni-Co9S8-60% exhibited the best supercapacitor performance, which was ascribed to the maximum Ni ion doping with morphology and structure retention, enhanced conductivity and stabilization of Co3+ in the structure. Therefore, Ni/Co-Zn batteries were fabricated by using a Zn plate as the anode and Ni-Co9S8-60% as the cathode, which deliver a high energy density of 256.5 W h kg-1 at the power density of 1.69 kW kg-1. Furthermore, the Ni/Co-Zn batteries exhibit a stable cycling after 3000 repeated cycles with capacitance retention of 69% at 4 A g-1. This encouranging result might provide a new perspective to optimize Co9S8-based electrodes with superior supercapacitor and Ni/Co-Zn battery performances.

20.
Molecules ; 27(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956777

RESUMO

Traditional grain size determination in materials characterization involves microscopy images and a laborious process requiring significant manual input and human expertise. In recent years, the development of computer vision (CV) has provided an alternative approach to microstructural characterization with preliminary implementations greatly simplifying the grain size determination process. Here, an end-to-end workflow to measure grain size in microscopy images without any manual input is presented. Following the ASTM standards for grain size determination, results from the line intercept (Heyn's method) and planimetric (Saltykov's method) approaches are used as the baseline. A pre-trained holistically nested edge detection (HED) model is used for CV-based edge detection, and the results are further compared to the classic Canny edge detection method. Post-processing was performed using open-source image processing packages to extract the grain size. In optical microscope images, the pre-trained HED model achieves much higher accuracy than the Canny edge detection method while reducing the image processing time by one to two orders of magnitude compared to traditional methods. The effects of morphological operations on the predicted grain size accuracy are also explored. Overall, the proposed end-to-end convolutional neural network (CNN)-based workflow can significantly reduce the processing time while maintaining the same accuracy as the traditional manual method.


Assuntos
Aprendizado Profundo , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Fluxo de Trabalho
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