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A molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom-up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C70, resulting in remarkable selective binding ability (K = 1.3 × 106 M-1) for C70 compared to C60 (K = 176 M-1), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave-convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes.
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This study explores the synthesis, structural characterization, and host-guest interactions of heteroatom bridged nanobelts, focusing on a cyclothianthrene nanobelt and a fused nanobelt incorporating thianthrene and phenoxathiin. Utilizing a cyclization-followed-by-bridging synthetic approach, both molecular belts were successfully synthesized, and their structures confirmed through NMR and MALDI-TOF-MS analysis. Crystallographic studies revealed that the cyclothianthrene nanobelt adopts an octagonal column-like conformation, while the hybrid belt forms an oval tub-shaped shape, both exhibiting distinct assembly motifs. The host-guest chemistry of these nanobelts was investigated with fullerenes (C60, C70, and PC61BM). The cyclothianthrene belt showed no interaction with these fullerenes, whereas the other belt demonstrated adaptive binding capabilities, forming stable complexes with C60 and C70 through π-π interactions and C-Hâ â â S hydrogen bonds. The binding constants indicated that the hybrid belt has a stronger affinity for C70 due to better size complementarity. Additionally, its interaction with PC61BM showcased a specific 1 : 1 binding mode despite exhibiting a smaller binding constant. This study underscores the impact of heteroatom incorporation on the structural and functional properties of nanobelts, offering insights for future molecular design strategies.
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A yellow pigmented, Gram-stain-positive, motile, facultatively anaerobic and irregular rod-shaped bacteria (strain M0-14T) was isolated from a till sample collected from the foreland of a high Arctic glacier near the settlement of Ny-Ålesund in the Svalbard Archipelago, Norway. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that M0-14T formed a lineage within the family Cellulomonadaceae, suborder Micrococcineae. M0-14T represented a novel member of the genus Pengzhenrongella and had highest 16S rRNA gene sequence similarity to Pengzhenrongella sicca LRZ-2T (97.3â%). Growth occurred at 4-25â°C (optimum 4-18â°C), at pH 6.0-9.0 (optimum pH 7.0), and in the presence of 0-5â% (w/v) NaCl. The predominant menaquinone was MK-9(H4) and the major fatty acids were anteiso-C15â:â0, C16â:â0 and summed feature 3 (comprising C16â:â1ω7c and/or C16â:â1ω6c). The major polar lipids were phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylinositol, one undefined phospholipid and five undefined phosphoglycolipids. The cell-wall diamino acid was l-ornithine whereas rhamnose and mannose were the cell-wall sugars. Polyphosphate particles were found inside the cells of M0-14T. Polyphosphate kinase and polyphosphate-dependent glucokinase genes were detected during genomic sequencing of M0-14. In addition, the complete pstSCAB gene cluster and phnCDE synthesis genes, which are important for the uptake and transport of phosphorus in cells, were annotated in the genomic data. According to the genomic data, M0-14T has a metabolic pathway related to phosphorus accumulation. The DNA G+C content of the genomic DNA was 70.8â%. On the basis of its phylogenetic relationship, phenotypic properties and chemotaxonomic distinctiveness, strain M0-14T represents a novel species of the genus Pengzhenrongella, for which the name Pengzhenrongella phosphoraccumulans sp. nov. is proposed. The type strain is M0-14T (= CCTCC AB 2012967T = NRRL B-59105T).
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Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Camada de Gelo , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Vitamina K 2 , RNA Ribossômico 16S/genética , Regiões Árticas , Ácidos Graxos/química , Vitamina K 2/análogos & derivados , DNA Bacteriano/genética , Camada de Gelo/microbiologia , Fosfolipídeos , SvalbardRESUMO
Ferroptosis is a type of lipid peroxidation-induced apoptosis brought on by imbalances in iron metabolism and redox. It involves both the thiol-associated anti-ferroptosis pathway and the excessive buildup of reactive oxygen species (ROS), which stimulates the ferroptosis pathway. Determining the precise control mechanism of ferroptosis requires examining the dynamic connection between reactive sulfur species (RSS) and ROS. Cysteine (Cys) and peroxynitrite (ONOO-) are highly active redox species in organisms and play dynamic roles in the ferroptosis process. In this study, a coumarin dye was conjugated with specific response sites for Cys and ONOO-, enabling the simultaneous detection of Cys and ONOO- through the green and red fluorescence channels, respectively (λem = 498 nm for Cys and λem = 565 nm for ONOO-). Using the probe LXB, we monitored the changes in Cys and ONOO- levels in the ferroptosis pathway induced by erastin. The results demonstrate a significant generation of ONOO- and a noticeable decrease in intracellular Cys levels at the beginning upon erastin treatment and finally maintains a relatively low level. This study presents the first probe to investigate the intracellular redox modulation and control between Cys and ONOO- during ferroptosis, providing valuable insights into the potential mutual correlation between Cys and ONOO- in this process.
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Cisteína , Ferroptose , Corantes Fluorescentes , Ácido Peroxinitroso , Ferroptose/efeitos dos fármacos , Corantes Fluorescentes/química , Cisteína/metabolismo , Cisteína/análise , Humanos , Ácido Peroxinitroso/análise , Ácido Peroxinitroso/metabolismo , Espectrometria de Fluorescência , Oxirredução , Piperazinas/farmacologia , Piperazinas/química , Cumarínicos/química , Cumarínicos/farmacologiaRESUMO
Mechanical forces play a crucial role in cellular processes, including ferroptosis, a form of regulated cell death associated with various diseases. However, the mechanical aspects of organelle lipid droplets (LDs) during ferroptosis are poorly understood. In this study, we designed and synthesized a fluorescent probe, TPE-V1, to enable real-time monitoring of LDs' viscosity using a dual-channel fluorescence-on model (red channel at 617 nm and NIR channel at 710 nm). The fluorescent imaging of using TPE-V1 was achieved due to the integrated mechanisms of the twisted intramolecular charge transfer (TICT) and aggregation-induced emission (AIE). Through dual-emission channel fluorescence imaging, we observed the enhanced mechanical energy of LDs triggering cellular mechanosensing, including ferroptosis and cell deformation. Theoretical calculations confirmed the probe's behavior, showing that high-viscosity media prevented the rotation processes and restored fluorescence quenching in low viscosity. These findings suggest that our TICT-TPE design strategy provides a practical approach to study LDs' mechanical properties during ferroptosis. This development enhances our understanding of the interplay between mechanical forces and LDs, contributing to the knowledge of ferroptotic cell death and potential therapeutic interventions targeting dysregulated cell death processes.
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Ferroptose , Corantes Fluorescentes , Gotículas Lipídicas , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Corantes Fluorescentes/química , Humanos , Imagem Óptica , Viscosidade , FluorescênciaRESUMO
OBJECTIVE: To investigate the effects of mid-pregnancy sleep deprivation (SD) in C57BL/6 J mice on the motor coordination of the offspring and to explore the potential mechanism of microglia activation in the cerebellar vermis of the offspring involved in the induction of impaired motor coordination development. METHODS: C57BL/6 J pregnant mice were randomly divided into the SD and control groups. SD was implemented by the multi-platform method from first day of the middle pregnancy (gestation day 8, GD8). At postnatal day 21 (PND21), we measured the development of motor behavior and collected cerebellar vermis tissues to observe the activation of microglia by H&E staining, the expression of microglia-specific markers ionized calcium-binding adaptor molecule-1 (Iba-1) and cluster of differentiation 68 (CD68) by immunohistochemical, and interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor -α (TNF-α) by real-time quantitative PCR (RT-qPCR). RESULTS: In the offspring of SD group, comparing to the control group, the total time of passage and the reverse crawl distance in the balance beam test, and the frequency of falls from the suspension cord was increased; with lower max rotational speed and shorter duration in the rotarod experiment. Further, we found that the microglia of cerebellar vermis tissues emerged an amoeba-like activation. The mean gray value of Iba-1 was lower, the density of positive cells of CD68 and the expression levels of IL-6 and TNF-α were increased. CONCLUSIONS: The motor coordination of offspring is impaired, accompanying a SD from mid-pregnancy, and the cerebellar vermis showed microglia activation and pro-inflammatory response. It suggested the adverse effects of SD from mid-gestation on the development of motor coordination through the inflammatory response in the cerebellar vermis of the offspring.
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Vermis Cerebelar , Microglia , Gravidez , Feminino , Camundongos , Animais , Microglia/metabolismo , Microglia/patologia , Vermis Cerebelar/metabolismo , Interleucina-6 , Privação do Sono/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Camundongos Endogâmicos C57BLRESUMO
Cyano- or CN-additions are often utilized in the design of photoacids to enhance and/or enable excited state proton transfer (ESPT) from the protic site to aqueous and nonaqueous solvents. In diprotic photoacid 8-amino-2-naphthol (8N2OH), the protonation state of the amino group (NH3+/NH2) acts as an on-off switch for ESPT at the OH site in water. This study investigated whether the addition of CN in 5-cyano-8-amino-2-naphthol (5CN8) could override this switch and promote new ESPT pathways. Analysis of the steady-state and time-resolved emission data showed that in the presence of protonated NH3+, CN enhances OH photoacidity (vs. in 8N2OH) and activates the ESPT pathway at NH3+. Both protic sites, OH and NH3+, can also donate a proton to methanol upon excitation. In contrast, in the presence of deprotonated NH2, despite the addition of CN, ESPT is still not observed at the OH site for 5CN8. Thus, the addition of CN cannot override or negate the inhibiting effect of NH2 on OH photoacidity. Potential causes for this inhibition are discussed, including electronic and antiaromaticity effects of CN and NH2 substitution.
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Precisely and automatically detecting the cough sound is of vital clinical importance. Nevertheless, due to privacy protection considerations, transmitting the raw audio data to the cloud is not permitted, and therefore there is a great demand for an efficient, accurate, and low-cost solution at the edge device. To address this challenge, we propose a semi-custom software-hardware co-design methodology to help build the cough detection system. Specifically, we first design a scalable and compact convolutional neural network (CNN) structure that generates many network instances. Second, we develop a dedicated hardware accelerator to perform the inference computation efficiently, and then we find the optimal network instance by applying network design space exploration. Finally, we compile the optimal network and let it run on the hardware accelerator. The experimental results demonstrate that our model achieves 88.8% classification accuracy, 91.2% sensitivity, 86.5% specificity, and 86.5% precision, while the computation complexity is only 1.09M multiply-accumulation (MAC). Additionally, when implemented on a lightweight field programmable gate array (FPGA), the complete cough detection system only occupies 7.9K lookup tables (LUTs), 12.9K flip-flops (FFs), and 41 digital signal processing (DSP) slices, providing 8.3 GOP/s actual inference throughput and total power dissipation of 0.93 W. This framework meets the needs of partial application and can be easily extended or integrated into other healthcare applications.
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The strong radioactivity of iodine compounds derived from nuclear power plant wastes has motivated the development of highly efficient adsorbents. Porous aromatic frameworks (PAFs) have attracted much attention due to their low density and diverse structure. In this work, an azo group containing PAF solid, denoted as LNU-58, was prepared through Suzuki polymerization of tris-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-phenyl)-amine and 3,5-dibromoazobenzene building monomers. Based on the specific polarity properities of the azo groups, the electron-rich aromatic fragments in the hierarchical architecture efficiently capture iodine molecules with an adsorption capacity of 3533.11 mg g-1 (353 wt%) for gaseous iodine and 903.6 mg g-1 (90 wt%) for dissolved iodine. The iodine uptake per specific surface area up to 8.55 wt% m-2 g-1 achieves the highest level among all porous adsorbents. This work illustrates the successful preparation of a new type of porous adsorbent that is expected to be applied in the field of practical iodine adsorption.
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Iodo , Adsorção , Aminas/química , Iodetos , PorosidadeRESUMO
Background: The purpose of this study was to investigate the predictive accuracy of erythrocyte count and maximum tumor diameter to maximum kidney diameter ratio (TKR) in patients with renal cell carcinoma (RCC). Methods: We retrospectively analyzed the clinicopathological epidemiological characteristics of patients with RCC in the First Hospital of Shanxi Medical University from 2010 to 2014. Among them, 295 cases with complete follow-up data at the time of visit were selected. We collected data including erythrocyte counts and length of each diameter line of the tumor and kidney. To predict the prognosis of RCC, receiver operating characteristic (ROC) curve analysis was used to calculate the cutoff value of each parameter. Results: Of the 295 included patients, 199 (67.5%) were male, 96 (32.5%) were female, and the mean (± SD) age was 56.45±11.03 years. The area under the curve (AUC) of the erythrocyte count and the TKR for predicting the prognosis of RCC were 0.672 (SD 0.031; P<0.001) and 0.800 (SD 0.030; P<0.001), respectively. When the cutoff value of the erythrocyte count and TKR count were 3.975 and 0.452, the highest Youden index values were 0.309 and 0.685, and the corresponding sensitivity and specificity were 0.826 and 0.685, and 0.483 and 1.000, respectively. Conclusions: An erythrocyte count <3.975×1012/L and a TKR >0.452 were found to be risk factors for poor prognosis in patients with RCC.
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An unprecedented zirconium metal-organic framework featuring a T-shaped benzimidazole strut was constructed and employed as a sponge-like material for selective absorption of macrocyclic guests. The neutral benzimidazole domain of the as-synthesized framework can be readily protonated and fully converted to benzimidazolium. Mechanical threading of [24]crown-8 ether wheels onto recognition sites to form pseudorotaxanes was evidenced by solution nuclear magnetic resonance, solid-state fluorescence, and infrared spectroscopy. Selective absorption of [24]crown-8 ether rather than its dibenzo counterpart was also observed. Further study reveals that this binding process is reversible and acid-base switchable. The success of docking macrocyclic guests in crystals via host-guest interactions provides an alternative route to complex functional materials with interpenetrated structures.
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A mechanically interlocked [3]rotaxane was newly designed, synthesized, and employed as a ligand for constructing metal-organic frameworks (MOFs). The nano-confinement by macrocycles forces the soft bis-isophthalate axle into a pseudo-rigid conformation and coordinates to zinc(II) ions, affording a two- or three-dimensional MOF under controlled conditions. The 2D MOF exhibits a neutral framework with a periodic puckering sheet structure, while an anionic framework with a pts topology was observed for the 3D MOF. The phase purity of both bulk materials was confirmed by powder X-ray diffraction. Thermogravimetric analysis reveals that both materials are stable up to 250 °C. The success of applying mechanical bonds to rigidify flexible ligands provides new insights for the design of metal-organic frameworks.
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An unprecedented molecular pumping cassette was designed and implemented for the construction of molecular necklaces, that is, radial [n]catenanes. The mechanism was fully confirmed on a model [2]pseudorotaxane, and the novel clipping-followed-by-pumping strategy was used to prepare a series of [n]catenanes (n = 2-5). A pair of [3]catenane diastereomers sequentially threaded with two different wheels was also accomplished. The success of utilizing molecular pumping to construct molecular necklaces offers new insights into complex molecular architectures and expands the application of molecular machines in synthesis.
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Two unprecedented isomeric macrocycles, a tubular belt and a Möbius strip, with thianthrene joints have been constructed through a one-step cyclization reaction. Both structures are fully characterized by NMR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction. A complexation study reveals that the tubular belt is a container for electron deficient guests. The Möbius strip exhibits twist-migration dynamics, which can be regulated by a sodium ion. Their facile synthesis, unique structure, and diverse host-guest chemistry enrich the belt chemistry.
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Porous carbon nanofibers with unique hierarchical structures have great potential in many fields, including heterogeneous catalysis, optoelectronics, and sensing. However, several preparation issues, such as additional templates, complicated processes, and harsh conditions, seriously hamper their widespread use. Here, we control the Sonogashira coupling reaction of linear building monomersâ1,4-dibromaphthalene and 1,4-ethylbenzeneâat the molecular level. Due to the occurrence of branching chain reaction (side reaction), 1D oligomer expands the growth orientation in the plane direction, forming a curled 1D fiber polymer. After thermal-driven skeleton engineering, porous carbon nanofibers were obtained with hierarchical channels of macro- (150 nm), meso- (5.2 nm), and microcavities (0.5 and 1.3 nm). The integration of macro-/meso-/microporous structure reveals a fast and sufficient interaction with electrolyte molecules, facilitating the construction of high-performance electrical devices. Our strategy, using a side reaction to achieve the dimensionality control of 1D copolymerization, paves a new way for the facile preparation of porous carbon nanofibers.
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Nitrogen-rich porous networks with additional polarity and basicity may serve as effective adsorbents for the Lewis electron pairing of iodine molecules. Herein a carbazole-functionalized porous aromatic framework (PAF) was synthesized through a Sonogashira-Hagihara cross-coupling polymerization of 1,3,5-triethynylbenzene and 2,7-dibromocarbazole building monomers. The resulting solid with a high nitrogen content incorporated the Lewis electron pairing effect into a π-conjugated nano-cavity, leading to an ultrahigh binding capability for iodine molecules. The iodine uptake per specific surface area was ~8 mg m-2 which achieved the highest level among all reported I2 adsorbents, surpassing that of the pure biphenyl-based PAF sample by ca. 30 times. Our study illustrated a new possibility for introducing electron-rich building units into the design and synthesis of porous adsorbents for effective capture and removal of volatile iodine from nuclear waste and leakage.
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Cyclothianthrenes, a series of sulphur-embedded hydrocarbon belts proposed a decade ago, were successfully constructed through a stepwise bottom-up synthesis. The belt [6]cyclothianthrene ([6]CT) is the smallest and most strained member of the family yet reported. Both [6]CT and [8]CT are the first examples of cyclothianthrene characterized by single crystal X-ray diffraction. An unprecedented chiral belt [7]CT and a Möbius-shaped [9]CT were also achieved via modular synthesis. Crystallographic and computational studies show that belts [6]CT-[8]CT have prism-like conformations with well-defined tubular cavities which have potential for guest molecule inclusion. Cyclic voltammograms further revealed that these belts are redox-active. The success of constructing sulphur-embedded hydrocarbon belts, that is, cyclothianthrenes, greatly enriches the chemistry of heteroatom-doped molecular belts and tubes.
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Hoop-shaped or belt-like molecules have been fascinating not only due to their challenging synthesis, but also unique physical and chemical properties. The incorporation of heteroatoms (N, O, S, etc.) into these belts could alter both molecular structures and electronic properties which will lead to versatile applications, from advanced host-guest systems to functional materials. Despite numerous computational studies, the synthesis and characterization of heteroatom-bridged double-stranded molecular belts remains scarce. Here we report the synthesis, crystal structure, and host-guest chemistry of two novel heteroatom-bridged belt-like macrocycles composed of phenoxathiin. The bowl-shaped belt demonstrates a strong binding affinity (Ka = 3.6 × 109 Mâ2) towards fullerene C60 and forms a 2:1 capsule-like complex with the aid of CâH···S hydrogen bonds. The column-like belt can bind the cyclic guest [2,2]paracyclophane to form a ring-in-ring complex. The modular synthesis, structural specificity, and diverse host-guest chemistry of cyclophenoxathiins markedly expands the known chemistry of molecular belts.
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On the basis of the mechanism of acylhydrazone compounds inhibiting the assembly of TMV CP and the unique structural characteristics of diketopiperazine ring, a series of optically pure indole diketopiperazine acylhydrazone were designed and synthesized. In order to systematically study the effect of the spatial configuration of the compounds on the antiviral activity, four compounds with different spatial configurations at C6 and C12a were also prepared. The bioassay results indicated that most of these new compounds displayed moderate to good antiviral activity, among which compounds 23, 25, 27, 28, 31, and 5d showed a significantly higher activity than that of commercial ribavirin. An in-depth structure-activity relationship investigation showed that the spatial conformation was one of the most important factors in adjusting antiviral activity; the research results provided information about the possible optimum configuration for interaction of this molecular with its target protein. At the same time, these new compounds also exhibited broad-spectrum fungicidal activities against 14 kinds of phytopathogenic fungi. What's more, some of these compounds exhibited good insecticidal activity to Plutella xylostella and Culex pipiens pallens.
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Antivirais/síntese química , Antivirais/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Inseticidas/síntese química , Inseticidas/farmacologia , Animais , Antivirais/química , Culex/efeitos dos fármacos , Culex/crescimento & desenvolvimento , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Desenho de Fármacos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/química , Hidrazonas/química , Hidrazonas/farmacologia , Indóis/química , Indóis/farmacologia , Inseticidas/química , Lepidópteros/efeitos dos fármacos , Lepidópteros/crescimento & desenvolvimento , Estrutura Molecular , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Vírus do Mosaico do Tabaco/crescimento & desenvolvimentoRESUMO
Eu/BiVO4 photocatalyst was synthesized by a facile one-step hydrothermal method. The structures and morphologies of Eu/BiVO4 photocatalysts were investigated by XRD, SEM and FT-IR and their photocatalytic activity was evaluated by the degradation of tetracycline hydrochloride (TCH) under the visible light irradiation. From the photocatalytic activity test, 1% Eu/BiVO4 displayed more superior photodegradation efficiency with 91.4% degradation efficiency of TCH in 150 min by contrast with 77.3% degradation rate of pure BiVO4. The mechanism has been explored that h+ is the primary active species, and ·OH is a secondary active substance in the photocatalytic process.