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A novel Fe-catalyzed fluorosulfonylation of alkenes with Na2S2O4 and N-fluorobenzenesulfonimide (NFSI) for assembling various lactam-functionalized alkyl sulfonyl fluorides is disclosed. In this reaction, Na2S2O4 acts as both an SO2 source and a reductant. Furthermore, the resulting products can be efficiently transformed into valuable chemicals, including sulfonyl esters and sulfonamides, via the sulfur(VI) fluoride exchange (SuFEx) click reaction. Preliminary mechanistic studies suggest that the transformation proceeds through intramolecular radical cyclization, SO2 insertion, sulfite anion formation, and fluorination.
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Disposal of electrolytes from waste lithium-ion batteries (LIBs) has gained much more attention with the growing application of LIBs, yet handling spent electrolyte is challengeable due to its high toxicity and the lack of established methods. In this study, a novel two-stage thermal process was developed for treating residual electrolytes resulted from spent lithium-ion batteries. The conversion of fluorophosphate and organic matter in oily electrolyte during low-temperature rotation distillation was investigated. The distribution and migration of the concentrated electrolytes were studied and the corresponding reaction mechanisms were elucidated. Additionally, the influence of alkali on the fixation of fluorine and phosphate was further examined. The results indicated that hydrolyzed carbonate esters and lithium in the electrolyte could combine to form Li2CO3 and the hydrolysable hexafluorophosphate was proven to be stable in the concentrated electrolyte (45 rpm/85 °C, 30 min). It was found that CO2, CO, CH4, and H2 were the primary pyrolysis gases, while the pyrolysis oil consisted of extremely flammable substances formed by the dissociation and recombination of chemical bonds in the electrolyte solvent. After pyrolysis at 300 °C, fluorine and phosphate were present in the form of sodium fluoride and sodium phosphate. The stability of the residue was enhanced, and the environmental risk was reduced. By adding alkali (KOH/Ca(OH)2, 20 %), hexafluorophosphate in the electrolyte was transformed into fluoride and phosphate in the residue, thereby reducing the device's corrosion from fluorine-containing gas. This study provides a viable approach for managing the residual electrolyte in the waste lithium battery recovery process.
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Suministros de Energía Eléctrica , Electrólitos , Litio , Litio/química , Electrólitos/química , Residuos Electrónicos/análisis , Pirólisis , Administración de Residuos/métodosRESUMEN
Background: Compare the anesthesia effects of combined intravenous and inhalation anesthesia (CIVIA) and total intravenous anesthesia (TIVA) in laparoscopic surgery. Furthermore, our objective is to examine the elements that contribute to the delay in postoperative recovery of neurocognitive function and anticipate the manifestation of delayed recovery by analyzing serum cytokines. Methods: The CIVIA group and the TIVA group both consisted of 130 patients who were scheduled to have elective major abdominal surgery through laparoscopy. The criteria taken into account by the observational and record-keeping study were the patients' ages, sexes, body masses, heights, and the presence or absence of any preexisting problems. Both groups also had their anesthetic depth, duration, and per-unit-of-time muscle relaxant and analgesic dosages recorded. Finally, the length of each patient's stay in the hospital as well as their overall length of stay were tracked. By using the Mini-Mental State Examination (MMSE) to measure cognitive function, we assessed the mental states of the subjects. Additionally, we wanted to identify any biomarkers that could be linked to postoperative cognitive decline or delays in neurocognitive recovery. Results: A total of 51 participants from the CIVIA group and 53 participants from the TIVA group satisfactorily completed the necessary neuropsychological exam for identifying delayed neurocognitive recovery at the study's completion. In the initial data of the two groups, no significant discrepancies were found (p > 0.05). The CIVIA group exhibited noteworthy reductions in the quantity of administered analgesics and muscle relaxants per unit of time in comparison to the TIVA group (p < 0.05). In addition to this, the duration from the sevoflurane tank being closed to the extubation period demonstrated a significant reduction in the CIVIA group compared to the TIVA group (p < 0.05). Moreover, no statistically notable distinction was observed in terms of postoperative hospitalization duration and overall hospitalization duration among both groups (p > 0.05). According to the study, both the CIVIA group and the TIVA group had a total of 7 (13.72%) and 17 (32.07%) individuals, respectively, who met the criteria for neurocognitive delayed recovery (Odds Ratio: 0.336; 95% CI: 0.134-0.864; p = 0.026). According to the research findings, it is indicated that there is a possibility for an increased presence of IL-6 in the bloodstream within 60 min following the incision made on the skin. This occurrence subsequently leads to the prolonged restoration of neurocognitive capabilities. Conclusion: The CIVIA technique outperforms the TIVA method in terms of overall assessment in the setting of laparoscopic surgery. It's also important to remember that an increased blood IL-6 level during laparoscopy may operate as a separate risk factor for a delay in the restoration of neurocognitive function.
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BACKGROUND: Current evidence shows that human induced pluripotent stem cells (hiPSCs) can effectively differentiate into keratinocytes (KCs), but its effect on skin burn healing has not been reported. AIM: To observe the effects of hiPSCs-derived KCs transplantation on skin burn healing in mice and to preliminarily reveal the underlying mechanisms. METHODS: An analysis of differentially expressed genes in burn wounds based on GEO datasets GSE140926, and GSE27186 was established. A differentiation medium containing retinoic acid and bone morphogenetic protein 4 was applied to induce hiPSCs to differentiate into KCs. The expression of KCs marker proteins was detected using immunofluorescence staining. A model of a C57BL/6 mouse with deep cutaneous second-degree burn was created, and then phosphate buffered saline (PBS), hiPSCs-KCs, or hiPSCs-KCs with knockdown of COL7A1 were injected around the wound surface. The wound healing, re-epithelialization, engraftment of hiPSCs-KCs into wounds, proinflammatory factor level, and the NF-κB pathway proteins were assessed by hematoxylin-eosin staining, carboxifluorescein diacetate succinimidyl ester (CFSE) fluorescence staining, enzyme linked immunosorbent assay, and Western blotting on days 3, 7, and 14 after the injection, respectively. Moreover, the effects of COL7A1 knockdown on the proliferation and migration of hiPSCs-KCs were confirmed by immunohistochemistry, EdU, Transwell, and damage repair assays. RESULTS: HiPSCs-KCs could express the hallmark proteins of KCs. COL7A1 was down-regulated in burn wound tissues and highly expressed in hiPSCs-KCs. Transplantation of hiPSCs-KCs into mice with burn wounds resulted in a significant decrease in wound area, an increase in wound re-epithelialization, a decrease in proinflammatory factors content, and an inhibition of NF-κB pathway activation compared to the PBS group. The in vitro assay showed that COL7A1 knockdown could rescue the inhibition of hiPSCs-KCs proliferation and migration, providing further evidence that COL7A1 speeds up burn wound healing by limiting cell proliferation and migration. CONCLUSION: In deep, second-degree burn wounds, COL7A1 can promote KC proliferation and migration while also suppressing the inflammatory response.
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A Pd-catalyzed multicomponent cross-coupling of allyl esters with alkyl bromides to synthesize allylic sulfones by using K2S2O5 as a connector is first reported. The reaction displays a broad range of substrate generality along with excellent functional group compatibility and produces the products with high regioselectivity (only E). Furthermore, the biologically active molecules with a late-stage modification, including aspirin, menthol, borneol, and estrone, are also highly compatible with the multicomponent cross-coupling reaction. Mechanistic studies indicate that the process of SO2 insertion into the C-Pd bond was involved in this transformation.
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Through the synergies of a heterogeneous synthetic approach and a homogeneous synthetic methodology, N-containing organic compounds can be synthesized via activated N-containing species prepared from N2 gas and suitable carbon sources. From N2 , carbon, and LiH, we have previously succeeded in the high-yield preparation of Li2 CN2 as the activated N-containing species. In this work, we applied Li2 CN2 as a novel synthetic synthon for constructing N-containing organic compounds. A series of reaction models, including a substitution reaction, cycloaddition reaction, and transition metal-catalyzed coupling reaction, were successfully performed using Li2 CN2 under mild conditions. Various valuable cyanamides, carbodiimides, N-aryl cyanamides and 1,2,4-triazole derivatives were readily synthesized in moderate to excellent yields. With this method, the 15 N-labeled products, including oxazolidine derivatives with anti-cancer activity, could also be facilely prepared from 15 N2 gas.
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A novel multicomponent sulfonylation of alkenes is described for the assembly of various ß-substituted arylsulfones using cheap and easily available K2S2O5 as a sulfur dioxide source. Of note, the procedure does not need any extra oxidants and metal catalysts and exhibits a relatively wide substrate scope and good functional group compatibility. Mechanistically, an initial arylsulfonyl radical is formed involving the insertion of sulfur dioxide with aryl diazonium salt, followed by alkoxyarylsulfonylation or hydroxysulfonylation of alkenes.
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Hypersaline wastewater is a typical industrial wastewater produced by iron and steel metallurgy, food material processing and other industries. Aiming at a waste liquid produced by mechanical vapour recompression evaporation and concentration in Tianjin coastal industrial zone, an environment-friendly supercritical water oxidation technology was used to efficiently remove the high-content organic matter in the hypersaline wastewater concentrate (HWC). A comparison of the degradation effects of various oxidants in the supercritical state showed that hydrogen peroxide (H2O2) could be used as a suitable agent for processing the HWC. The reaction parameters were systematically optimised by single-factor experiment and response surface design. The degradation mechanism and reaction characteristics were analyzed using gas chromatography mass spectrometry. Solid residues were characterised by field emission scanning electron microscope. The results indicated that when the dosage of hydrogen peroxide was 6.39%, the reaction temperature was 380°C, the reaction time was about 90â min and the optimal total organic carbon removal rate was 96.22%. Furthermore, it was found that hydroxyl radicals produced by hydrogen peroxide initiated the bond breaking and ring-opening reactions in organic matter, which eventually degraded organic matter into water and carbon dioxide.
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Aguas Residuales , Contaminantes Químicos del Agua , Eliminación de Residuos Líquidos/métodos , Peróxido de Hidrógeno/química , Compuestos Orgánicos , Oxidación-Reducción , Agua , Contaminantes Químicos del Agua/químicaRESUMEN
A new method involving mild acryl transient-chelating-group-controlled stereoselective Rh(i)-catalyzed silylative aminocarbonylation of 2-alkynylanilines with CO and silanes is presented for producing (Z)-3-(silylmethylene)indolin-2-ones. Upon using an acryl transient chelating group, 2-alkynylanilines undergo an unprecedented alkyne cis-silylrhodation followed by aminocarbonylation to assemble (Z)-3-(silylmethylene)indolin-2-ones. Mechanistic studies show that acryl transient chelating effects result in the key alkyne cis-silylrhodation process.
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OBJECTIVE: This study aimed to evaluate timing of fixation to retard bone absorption using finite element analysis(FEA). METHODS: Volunteer CT images were used to construct four models of mandibles with varying degrees of alveolar bone resorption. By simulating occlusal force loading, biomechanical analysis was made on the periodontal membrane, tooth root and surrounding bone (both cancellous and cortical) of mandibular dentition. RESULTS: The von Mises stress value of the periodontal structures was positively related with the degree of alveolar bone resorption, and the von Mises stress at the interface between the periodontal membrane and tooth root was increased significantly in moderate to severe periodontitis models. The von Mises stress at the interface between the periodontal cortical bone and cancellous bone was increased significantly in the severe periodontitis model. And the von Mises stress value with oblique loading showed significantly higher than vertical loading. CONCLUSION: Teeth with moderate to severe periodontitis, loosened tooth fixation can be used to retard bone absorption.
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Pérdida de Hueso Alveolar , Periodontitis , Raíz del Diente , Pérdida de Hueso Alveolar/diagnóstico por imagen , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Mandíbula , Estrés Mecánico , Raíz del Diente/cirugíaRESUMEN
A novel copper-catalyzed cross-coupling of arylsulfonyl radicals with diazo compounds is described for the synthesis of various arylsulfones under mild conditions. In this reaction, the cheap, environmentally friendly, and readily available inorganic K2S2O5 is employed as the sulfur dioxide source for providing arylsulfonyl radicals. In addition, a radical mechanism involving the insertion of sulfur dioxide with aryl radicals followed by the coupling of arylsulfonyl radicals with copper carbenes is proposed.
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Cobre , Dióxido de Azufre , Compuestos Azo , Catálisis , Estructura MolecularRESUMEN
Arachnida is an exceptionally diverse class in the Arthropoda, consisting of 20 orders and playing crucial roles in the terrestrial ecosystems. However, their interordinal relationships have been debated for over a century. Rearranged or highly rearranged mitochondrial genomes (mitogenomes) were consistently found in this class, but their various extent in different lineages and efficiency for resolving arachnid phylogenies are unclear. Here, we reconstructed phylogenetic trees using mitogenome sequences of 290 arachnid species to decipher interordinal relationships as well as diversification through time. Our results recovered monophyly of ten orders (i.e. Amblypygi, Araneae, Ixodida, Mesostigmata, Opiliones, Pseudoscorpiones, Ricinulei, Sarcoptiformes, Scorpiones and Solifugae), while rejecting monophyly of the Trombidiformes due to the unstable position of the Eriophyoidea. The monophyly of Acari (subclass) was rejected, possibly due to the long-branch attraction of the Pseudoscorpiones. The monophyly of Arachnida was further rejected because the Xiphosura nested within arachnid orders with unstable positions. Mitogenomes that are highly rearranged in mites but less rearranged or conserved in the remaining lineages point to their exceptional diversification in mite orders; however, shared derived mitochondrial (mt) gene clusters were found within superfamilies rather than interorders, confusing phylogenetic signals in arachnid interordinal relationships. Molecular dating results show that arachnid orders have ancient origins, ranging from the Ordovician to the Carboniferous, yet have significantly diversified since the Cretaceous in orders Araneae, Mesostigmata, Sarcoptiformes, and Trombidiformes. By summarizing previously resolved key positions of some orders, we propose a plausible arachnid tree of life. Our results underline a more precise framework for interordinal phylogeny in the Arachnida and provide new insights into their ancient evolution.
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Arácnidos , Genoma Mitocondrial , Ácaros , Animales , Arácnidos/genética , Ecosistema , Genoma Mitocondrial/genética , FilogeniaRESUMEN
A novel and mild metal-free catalyzed radical-mediated cascade spirocyclization of N-benzylacrylamides with polyhaloalkanes is proposed for the preparation of polyhalo-substituted azaspirocyclohexadienones. Notably, polyhaloalkanes are employed as efficient alkyl radical sources via the cleavage of C(sp3)-H bonds. This protocol undergoes a cascade radical addition and intramolecular cyclization/dearomatization process, and enables the easy construction of multiple chemical bonds and a spiro ring in a single reaction.
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Compuestos de Espiro , Ciclización , Radicales Libres , Compuestos de Espiro/químicaRESUMEN
The element nitrogen and nitrogenous compounds are vital to life. The synthesis of nitrogen-containing compounds using dinitrogen as the nitrogen source, not through ammonia, is of great interest and great value but remains a grand challenge. Herein, we describe a strategy to realize this transformation by combining the heterogeneous approach with the homogeneous methodology. The N2 molecule was first fixed with carbon and LiH through a one-pot heterogeneous process, forming Li2CN2 as an 'activated' nitrogen source with high efficiency. Then subsequent homogeneous treatments of Li2CN2 to construct the organic synthon carbodiimide and the RNA/DNA building block pyrimidines were fulfilled. By using 15N2 as the feedstock, their corresponding 15N-labeled carbodiimide and pyrimidines were readily obtained. This homogeneous-heterogeneous synergy strategy will open a new chapter for N2 transformation.
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An efficient palladium-catalyzed difunctionalization/dearomatization of N-benzylacrylamides with α-carbonyl alkyl bromides as alkyl radical precursors has been described. Various α-carbonyl alkyl bromides, including α-bromoalkyl esters and ketones, reacted smoothly to provide important azaspirocyclohexadienones in moderate to excellent yields. In addition, mechanistic studies suggested that the reaction proceeded via a radical pathway.
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Nanoparticles released into the environment are attracting increasing concern because of their potential toxic effects. Conventional methods for assessing the toxicity of nanoparticles are usually confined to cultivable cells, but not applicable to viable but non-culturable (VBNC) cells. However, it remains unknown whether silver nanoparticles (AgNPs), a typical antimicrobial agent, could induce bacteria into a VBNC state in natural environments. In this work, the viability of E. coli, an indicator bacterium widely used for assessing the antibacterial activity of AgNPs, was examined through coupling plate counting, fluorescence staining and adenosine triphosphate (ATP) production. AgNPs were found to have a considerable antibacterial ability, which resulted in less than 0.0004% of culturable cells on plates. However, more than 80% of the cells still maintained their cell membrane integrity under the stress of 80 mg/L AgNPs. Meanwhile, the residue of ATP production (0.6%) was 1500 times higher than that of the culturable cells (< 0.0004%). These results clearly demonstrate that when exposed to AgNPs, most of cells fell into a VBNC state, instead of dying. Environmental factors, e.g., Cl- and illumination, which could change the dissolution, hydrophilicity and zeta potential of AgNPs, eventually influenced the culturability of E. coli. Inhibition of dissolved Ag+ and reactive oxygen species was found to facilitate the mitigation of the strain into a VBNC state. Our findings suggest the necessity of re-evaluating the environmental effects and antibacterial activities of AgNPs.
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Escherichia coli , Nanopartículas del Metal , Antibacterianos/toxicidad , Supervivencia Celular , Nanopartículas del Metal/toxicidad , Plata/toxicidadRESUMEN
BACKGROUND: Liver cancer stem cells (LCSCs) play key roles in the metastasis, recurrence, and chemotherapeutic resistance of hepatocellular carcinoma (HCC). Our previous research showed that the POSTN gene is closely related to the malignant progression and poor prognosis of HCC. This study aimed to elucidate the role of POSTN in generating LCSCs and maintaining their stemness as well as the underlying mechanisms. METHODS: Human HCC tissues and matched adjacent normal tissues were obtained from 110 patients. Immunohistochemistry, western blotting (WB), and RT-PCR were performed to detect the expression of POSTN and stemness factors. The roles of transforming growth factor (TGF)-ß1 and AP-2α in the POSTN-induced stemness transformation of HCC cells were explored in vitro and in vivo using LCSCs obtained by CD133+ cell sorting. RESULTS: The high expression of POSTN was correlated with the expression of various stemness factors, particularly CD133, in our HCC patient cohort and in TCGA and ICGC datasets. Knockdown of POSTN expression decreased the abilities of HCC cell lines to form tumours in xenograft mouse models. Knockdown of POSTN expression also suppressed cell viability and clone formation, invasion, and sphere formation abilities in vitro. Knockdown of AP-2α attenuated the generation of CD133+ LCSCs and their malignant behaviours, indicating that AP-2α was a critical factor that mediated the POSTN-induced stemness transformation and maintenance of HCC cells. The role of AP-2α was verified by using a specific αvß3 antagonist, cilengitide, in vitro and in vivo. Activation of POSTN could release TGFß1 from the extracellular matrix and initiated POSTN/TGFß1 positive feedback signalling. Furthermore, we found that the combined use of cilengitide and lenvatinib suppressed the growth of HCC cells with high POSTN expression more effectively than the use of lenvatinib alone in the patient-derived xenograft (PDX) mouse model. CONCLUSIONS: The POSTN/TGFß1 positive feedback pathway regulates the expression of stemness factors and the malignant progression of HCC cells by regulating the transcriptional activation of AP-2α. This pathway may serve as a new target for targeted gene therapy in HCC.
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Carcinoma Hepatocelular/metabolismo , Moléculas de Adhesión Celular/metabolismo , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Factor de Transcripción AP-2/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Adulto , Animales , Carcinoma Hepatocelular/patología , Proliferación Celular/fisiología , Modelos Animales de Enfermedad , Retroalimentación Fisiológica , Xenoinjertos , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Células Madre Neoplásicas/patologíaRESUMEN
Fructus arctii is commonly used in Chinese medicine, and arctiin and arctigenin are its main active ingredients. Arctiin has low bioavailability in the human body and needs to be converted into arctigenin by intestinal microbes before it can be absorbed into the blood. Arctigenin has antiviral, anti-inflammatory, and anti-tumour effects and its development has important value. In this study, we used external microbial fermentation with Aspergillus awamori and Trichoderma reesei to process and convert arctiin from F. arctii powder into arctigenin, hence increasing its bioavailability. We developed a fermentation process by optimising the carbon and nitrogen source/ratio, fermentation time, pH, liquid volume, inoculation volume, and substrate solid-liquid ratio. This allowed for an arctiin conversion rate of 99.84%, and the dissolution rate of the final product was 95.74%, with a loss rate as low as 4.26%. After the fermentation of F. arctii powder, the average yield of arctigenin is 19.51 mg/g. Crude fermented F. arctii extract was purified by silica gel column chromatography, and we observed an arctigenin purity of 99.33%. Our technique effectively converts arctiin and extracts arctigenin from F. arctii and provides a solid basis for further development and industrialisation.
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Environmental pollution caused by antibiotic resistance genes (ARGs) has attracted wide concerns, and various approaches have been proposed to control ARGs dissemination. TiO2 photoexcitation under UV irradiation has been used for such a purpose. But the actual UV intensity is insufficient to trigger the production of reactive oxygen species (ROS) in the aqueous environment. Thus, it is interesting to know how mild photoexcitation of TiO2 with low-intensity UV affects the horizontal transfer of ARGs. In this work, the impact of TiO2 photoexcitation on the transductant efficiency of constructed filamentous phage gM13 to its host Escherichia coli TG1 was investigated. Although individual treatment with nano-TiO2 and UV irradiation both improved the phage infection, TiO2 photoexcitation exhibited a clear synergistic promotion effect. However, excessive UV irradiation resulted in a decrease in transductant formation, implying severe oxidative damage to the phage and bacterial cells. Extracellular ROS produced by moderate photoexcitation of TiO2 could increase the outer membrane permeability, which facilitated phage infection. The increase in pili synthesis induced by intracellular ROS provided more sites for phage recognition and invasion in the presence of TiO2 photoexcitation, which contributed to the transduction process. Our work provides a novel insight into the impact of TiO2 photoexcitation on ARGs diffusion and is helpful for better understanding non-toxic environmental effect of nanomaterials.