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BACKGROUND: Tumor-infiltrating lymphocyte (TIL) therapy has been restricted by intensive lymphodepletion and high-dose intravenous interleukin-2 (IL-2) administration. To address these limitations, we conducted preclinical and clinical studies to evaluate the safety, antitumor activity, and pharmacokinetics of an innovative modified regimen in patients with advanced gynecologic cancer. METHODS: Patient-derived xenografts (PDX) were established from a local recurrent cervical cancer patient. TILs were expanded ex vivo from minced tumors without feeder cells in the modified TIL therapy regimen. Patients underwent low-dose cyclophosphamide lymphodepletion followed by TIL infusion without intravenous IL-2. The primary endpoint was safety; the secondary endpoints included objective response rate, duration of response, and T cell persistence. RESULTS: In matched patient-derived xenografts (PDX) models, homologous TILs efficiently reduced tumor size (p < 0.0001) and underwent IL-2 absence in vivo. In the clinical section, all enrolled patients received TIL infusion using a modified TIL therapy regimen successfully with a manageable safety profile. Five (36%, 95% CI 16.3-61.2) out of 14 evaluable patients experienced objective responses, and three complete responses were ongoing at 19.5, 15.4, and 5.2 months, respectively. Responders had longer overall survival (OS) than non-responders (p = 0.036). Infused TILs showed continuous proliferation and long-term persistence in all patients and showed greater proliferation in responders which was indicated by the Morisita overlap index (MOI) of TCR clonotypes between infused TILs and peripheral T cells on day 14 (p = 0.004) and day 30 (p = 0.004). Higher alteration of the CD8+/CD4+ ratio on day 14 indicated a longer OS (p = 0.010). CONCLUSIONS: Our modified TIL therapy regimen demonstrated manageable safety, and TILs could survive and proliferate without IL-2 intravenous administration, showing potent efficacy in patients with advanced gynecologic cancer. TRIAL REGISTRATION: NCT04766320, Jan 04, 2021.
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Interleucina-2 , Linfocitos Infiltrantes de Tumor , Humanos , Femenino , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Persona de Mediana Edad , Interleucina-2/administración & dosificación , Interleucina-2/uso terapéutico , Animales , Anciano , Adulto , Ratones , Neoplasias de los Genitales Femeninos/terapia , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Resultado del Tratamiento , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Inhibidores de Puntos de Control Inmunológico/uso terapéuticoRESUMEN
Objectives: To investigate the relationship between sublingual microcirculation and the prognosis of sepsis. Data sources: The PubMed, Web of Science, Embase, and China National Knowledge Infrastructure (CNKI) databases were searched to identify studies published from January 2003 to November 2023. Study selection: Clinical studies examining sublingual microcirculation and the prognosis of sepsis were included. Data extraction: Sublingual microcirculation indices included the microvascular blood index (MFI), total vascular density (TVD), perfusion vascular density (PVD), perfusion vascular vessel (PPV), and heterogeneity index (HI). Prognostic outcomes included mortality and severity. Funnel plots and Egger's test were used to detect publication bias. The ability of the small vessel PPV (PPVs) to predict sepsis-related mortality was analyzed based on the summary receiver operating characteristic (SROC) curve, pooled sensitivity, and pooled specificity. Data synthesis: Twenty-five studies involving 1750 subjects were included. The TVD (95% CI 0.11-0.39), PVD (95% CI 0.42-0.88), PPV (95% CI 6.63-13.83), and MFI (95% CI 0.13-0.6) of the survival group were greater than those of the nonsurvival group. The HI in the survival group was lower than that in the nonsurvival group (95% CI -0.49 to -0.03). The TVD (95% CI 0.41-0.83), PVD (95% CI 0.83-1.17), PPV (95% CI 14.49-24.9), and MFI (95% CI 0.25-0.66) of the nonsevere group were greater than those of the severe group. Subgroup analysis revealed no significant difference in TVD between the survival group and the nonsurvival group in the small vessel subgroup. The area under the SROC curve (AUC) was 0.88. Conclusions: Sublingual microcirculation was worse among patients who died and patients with severe sepsis than among patients who survived and patients with nonsevere sepsis. PPV has a good predictive value for the mortality of sepsis patients. This study was recorded in PROSPERO (registration number: CRD42023486349).
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In recent studies, carbon nanotube (CNTs) materials and their composites have demonstrated remarkable catalytic activity in the activation of persulfate (PS), facilitating the efficient degradation of organic pollutants. In this study, a novel Co loaded carbon nanotubes (CoO@CNT) catalyst was prepared to promote PDS activation for the degradation of sulfafurazole (SIZ). Experimental results, the CNT as a carrier effectively reduces the leaching of cobalt ions and improves the electron transport capacityï¼whereas the introduced Co effectively activates the PDS, promoting the generation of highly reactive radicals to degrade SIZ. Under optimized conditions (a catalyst dose of 0.2 g/L, a PDS dose of 1 g/L and an initial pH = 9.0), the obtained CoO@CNT demonstrated favorable Fenton-like performance, reaching a degradation efficiency of 95.55% within 30 min. Furthermore, density functional theory (DFT) calculations demonstrate that the introduction of cobalt (Co) accelerates electron transfer, promoting the decomposition of PDS while facilitating the Co2+/Co3+ redox cycling. We further employed the environmental chemistry and risk assessment system (ECOSAR) to evaluate the ecological toxicity of intermediate products, revealing a significant reduction in ecological toxicity associated with this degradation process, thereby confirming its environmental harmlessness. Through batch experiments and studies, we gained a comprehensive understanding of the mechanism and influencing factors of CoO@CNT in the role of SIZ degradation, and provided robust support for evaluating the ecological toxicity of degradation products. This study provides a significant strategy for the development of efficient catalysts incorporating Co for the environmentally friendly degradation of organic pollutants.
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Cobalto , Nanotubos de Carbono , Nanotubos de Carbono/química , Cobalto/química , Catálisis , Sulfatos/química , Óxidos/química , Contaminantes Químicos del Agua/química , Oxidación-ReducciónRESUMEN
In this study, CuFe2O4/CuS composite photocatalysts were successfully synthesized for the activation of peroxynomosulfate to remove ciprofloxacin from wastewater. The structural composition and morphology of the materials were analyzed by XRD, SEM, TEM, and Raman spectroscopy. The electrochemical properties of the samples were tested by an electrochemical workstation. The band gap of the samples was calculated by DFT and compared with the experimental values. The effects of different catalysts, oxidant PMS concentrations, and coexisting ions on the experiments were investigated. The reusability and stability of the photocatalysts were also investigated. The mechanism of the photocatalytic degradation process was proposed based on the free radical trapping experiment. The results show that the p-p heterojunction formed between the two contact surfaces of the CuFe2O4 nanoparticle and CuS promoted the charge transfer between the interfaces and inhibited the recombination of electrons and holes. CuFe2O4-5/CuS photocatalyst has the best catalytic activity, and the removal rate of ciprofloxacin is 93.7%. The intermediates in the degradation process were tested by liquid chromatography-mass spectrometry (LC-MS), and the molecular structure characteristics of ciprofloxacin were analyzed by combining with DFT calculations. The possible degradation pathways of pollutants were proposed. This study reveals the great potential of the photocatalyst CuFe2O4/CuS in the activation of PMS for the degradation of ciprofloxacin wastewater.
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Aguas Residuales , Contaminantes Químicos del Agua , Peróxidos/química , Ciprofloxacina , Contaminantes Químicos del Agua/química , OxidantesRESUMEN
The intestinal mucosal barrier is critical for the absorption of nutrients and the health of both humans and animals. Recent publications from clinical and experimental studies have shown the importance of the nutrients-bacteria-host interaction for the intestinal homeostasis. Dysfunction of these interactions has been reported to be associated with metabolic disorders and development of intestinal diseases such as the irritable bowel syndrome and inflammatory bowel diseases. Tryptophan and its metabolites, including kynurenine, kynurenic acid, and 5-hydroxytrptamine, can influence the proliferation of enterocytes, intestinal integrity, and immune response, as well as intestinal microbiota, therefore, regulating and contributing to the intestinal health. In this review, we highlight recent findings on the effect of tryptophan and its metabolites on the mucosal barrier and intestinal homeostasis and its regulation of innate immune response. Moreover, we present the signaling pathways related to Trp metabolism, such as mammalian target of rapamycin, aryl hydrocarbon receptor, and pregnane X receptor, which contribute to the intestinal homeostasis and discuss future perspectives on spontaneous interference in host tryptophan metabolism as potential clinical strategies of intestinal diseases.
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Microbioma Gastrointestinal , Microbiota , Animales , Inmunidad Innata , Mucosa Intestinal/metabolismo , Intestinos , Mamíferos , Triptófano/metabolismoRESUMEN
BACKGROUND: Bacteria are the main pathogens that cause sepsis. The pathogenic mechanisms of sepsis caused by gram-negative and gram-positive bacteria are completely different, and their prognostic differences in sepsis remain unclear. METHODS: The PubMed, Web of Science, Cochrane Library, and Embase databases were searched for Chinese and English studies (January 2003 to September 2023). Observational studies involving gram-negative (G (-))/gram-positive (G (+)) bacterial infection and the prognosis of sepsis were included. The stability of the results was evaluated by sensitivity analysis. Funnel plots and Egger tests were used to check whether there was publication bias. A meta-regression analysis was conducted on the results with high heterogeneity to identify the source of heterogeneity. A total of 6949 articles were retrieved from the database, and 45 studies involving 5586 subjects were included after screening according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Twenty-seven high-quality studies and 18 moderate-quality studies were identified according to the NewcastleâOttawa Scale score. There was no significant difference in the survival rate of sepsis caused by G (-) bacteria and G (+) bacteria (OR 0.95, 95% CI 0.70-1.28). Subgroup analysis according to survival follow-up time showed no significant difference. The serum concentrations of C-reactive protein (CRP) (SMD = 0.39, 95% CI 0.02-0.76), procalcitonin (SMD = 1.95, 95% CI 1.32-2.59) and tumor necrosis factor-alpha (TNF-α) (MD = 0.31, 95% CI 0.25-0.38) in the G (-) bacterial infection group were significantly higher than those in the G (+) bacterial infection group, but there was no significant difference in IL-6 (SMD = 1.33, 95% CI - 0.18-2.84) and WBC count (MD = - 0.15, 95% CI - 0.96-00.66). There were no significant differences between G (-) and G (+) bacteria in D dimer level, activated partial thromboplastin time, thrombin time, international normalized ratio, platelet count, length of stay or length of ICU stay. Sensitivity analysis of the above results indicated that the results were stable. CONCLUSION: The incidence of severe sepsis and the concentrations of inflammatory factors (CRP, PCT, TNF-α) in sepsis caused by G (-) bacteria were higher than those caused by G (+) bacteria. The two groups had no significant difference in survival rate, coagulation function, or hospital stay. The study was registered with PROSPERO (registration number: CRD42023465051).
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Infecciones Bacterianas , Sepsis , Humanos , Pronóstico , Factor de Necrosis Tumoral alfa , Bacterias Gramnegativas , Proteína C-Reactiva/análisis , Bacterias , Bacterias GrampositivasRESUMEN
BACKGROUND: Few-shot learning (FSL) is a class of machine learning methods that require small numbers of labeled instances for training. With many medical topics having limited annotated text-based data in practical settings, FSL-based natural language processing (NLP) holds substantial promise. We aimed to conduct a review to explore the current state of FSL methods for medical NLP. METHODS: We searched for articles published between January 2016 and October 2022 using PubMed/Medline, Embase, ACL Anthology, and IEEE Xplore Digital Library. We also searched the preprint servers (e.g., arXiv, medRxiv, and bioRxiv) via Google Scholar to identify the latest relevant methods. We included all articles that involved FSL and any form of medical text. We abstracted articles based on the data source, target task, training set size, primary method(s)/approach(es), and evaluation metric(s). RESULTS: Fifty-one articles met our inclusion criteria-all published after 2018, and most since 2020 (42/51; 82%). Concept extraction/named entity recognition was the most frequently addressed task (21/51; 41%), followed by text classification (16/51; 31%). Thirty-two (61%) articles reconstructed existing datasets to fit few-shot scenarios, and MIMIC-III was the most frequently used dataset (10/51; 20%). 77% of the articles attempted to incorporate prior knowledge to augment the small datasets available for training. Common methods included FSL with attention mechanisms (20/51; 39%), prototypical networks (11/51; 22%), meta-learning (7/51; 14%), and prompt-based learning methods, the latter being particularly popular since 2021. Benchmarking experiments demonstrated relative underperformance of FSL methods on biomedical NLP tasks. CONCLUSION: Despite the potential for FSL in biomedical NLP, progress has been limited. This may be attributed to the rarity of specialized data, lack of standardized evaluation criteria, and the underperformance of FSL methods on biomedical topics. The creation of publicly-available specialized datasets for biomedical FSL may aid method development by facilitating comparative analyses.
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Aprendizaje Automático , Procesamiento de Lenguaje Natural , PubMed , MEDLINE , PublicacionesRESUMEN
The research and development of absorbing materials with high absorbing capacity, wide effective absorption bandwidth, and lightweight has always been interesting. In this research, a facile hydrothermal method was used to prepare MnFe2O4, and the grain size of MnFe2O4 decreased with increasing hydrothermal temperature. When the size of MnFe2O4 nanoparticles is less than 10 nm, its quantum size effect and surface effect make its electromagnetic microwave absorption performance greatly optimized. When the thickness of MnFe2O4-110 °C is 2.57 mm, the minimum reflection loss (RLmin) is -35.28 dB. Based on this, light porous diatomite and a three-dimensional polyaniline network are introduced. Diatomite is used as the base material to effectively reduce the agglomeration of MnFe2O4 quantum dots. The relatively high surface area introduced by a three-dimensional network of polyaniline promotes the orientation, interfacial polarization, multiple relaxation, and impedance matching, thereby generating further dielectric loss. Additionally, the magnetic properties of manganese ferrite and the strong electrical conductivity of polyaniline play an appropriate complementary role in electromagnetic wave absorption. The RLmin of MnFe2O4/PANI/diatomite is -56.70 dB at 11.12 GHz with an absorber layer thickness of 2.57 mm. The effective frequency bandwidth (RL < -10 dB) ranges from 9.21 to 18.00 GHz. The absorption mechanism indicates that the high absorption intensity is the result of the synergistic effect of impedance matching, conduction losses, polarization losses, and magnetic losses.
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Illicit or 'designer' benzodiazepines are a growing contributor to overdose deaths. We employed natural language processing (NLP) to study benzodiazepine mentions over 10 years on 270 online drug forums (subreddits) on Reddit. Using NLP, we automatically detected mentions of illicit and prescription benzodiazepines, including their misspellings and non-standard names, grouping relative mentions by quarter. On a collection of 17â861â755 posts between 2012 and 2021, we searched for 26 benzodiazepines (8 prescription; 18 illicit), detecting 173â275 mentions. The rate of posts about both prescription and illicit benzodiazepines increased consistently with increases in deaths involving both drug classes, illustrating the utility of surveillance via Reddit.
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Benzodiazepinas , Sobredosis de Droga , Humanos , Sobredosis de Droga/epidemiologíaRESUMEN
BACKGROUND: Despite recent rises in fatal overdoses involving multiple substances, there is a paucity of knowledge about stimulant co-use patterns among people who use opioids (PWUO) or people being treated with medications for opioid use disorder (PTMOUD). A better understanding of the timing and patterns in stimulant co-use among PWUO based on mentions of these substances on social media can help inform prevention programs, policy, and future research directions. This study examines stimulant co-mention trends among PWUO/PTMOUD on social media over multiple years. METHODS: We collected publicly available data from 14 forums on Reddit (subreddits) that focused on prescription and illicit opioids, and medications for opioid use disorder (MOUD). Collected data ranged from 2011 to 2020, and we also collected timelines comprising past posts from a sample of Reddit users (Redditors) on these forums. We applied natural language processing to generate lexical variants of all included prescription and illicit opioids and stimulants and detect mentions of them on the chosen subreddits. Finally, we analyzed and described trends and patterns in co-mentions. RESULTS: Posts collected for 13,812 Redditors showed that 12,306 (89.1%) mentioned at least 1 opioid, opioid-related medication, or stimulant. Analyses revealed that the number and proportion of Redditors mentioning both opioids and/or opioid-related medications and stimulants steadily increased over time. Relative rates of co-mentions by the same Redditor of heroin and methamphetamine, the substances most commonly co-mentioned, decreased in recent years, while co-mentions of both fentanyl and MOUD with methamphetamine increased. CONCLUSION: Our analyses reflect increasing mentions of stimulants, particularly methamphetamine, among PWUO/PTMOUD, which closely resembles the growth in overdose deaths involving both opioids and stimulants. These findings are consistent with recent reports suggesting increasing stimulant use among people receiving treatment for opioid use disorder. These data offer insights on emerging trends in the overdose epidemic and underscore the importance of scaling efforts to address co-occurring opioid and stimulant use including harm reduction and comprehensive healthcare access spanning mental-health services and substance use disorder treatment.
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Estimulantes del Sistema Nervioso Central , Sobredosis de Droga , Metanfetamina , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Sobredosis de Droga/tratamiento farmacológico , Sobredosis de Droga/epidemiología , Fentanilo , Humanos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiologíaRESUMEN
Inorganic nitrogen (IN) and organic nitrogen (ON) molecules constitute a significant part of atmospheric aerosol. Unlike IN, the total ON quantity remains largely unquantified due to a lack of a simple and direct measurement method. This analytical deficiency hinders the quantitative assessment of the various environmental and health effect impacts by aerosol ON. In this work, we developed an analyzer system that utilizes programmed thermal evolution of carbonaceous and nitrogenous aerosols and chemiluminescence detection coupled with the multivariate curve resolution data treatment to achieve simultaneous quantification of IN and ON. The system is capable of detecting IN and ON as low as 96 ng N per sample on a small filter aliquot (1 cm2) without any pretreatment. This method breakthrough opens the door to quantifying an important pool of aerosol N that was analytically inaccessible in the past and holds the promise to quantifying IN and ON in other environmental samples. As a demonstration, quantification of aerosol ON at an urban site in Hong Kong, China, in samples spanning over a year reveals ON constituting a significant fraction (9-52%) of the total aerosol nitrogen and having major source origins in both secondary formation and primary emissions.
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Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Luminiscencia , Nitrógeno , Material Particulado/análisisRESUMEN
Humans have a limited postinjury regenerative ability. Therefore, cell-derived biomaterials have long been utilized for tissue repair. Cells with multipotent differentiation potential, such as stem cells, have been administered to patients for the treatment of various diseases. Researchers expected that these cells would mediate tissue repair and regeneration through their multipotency. However, increasing evidence has suggested that in most stem cell therapies, the paracrine effect but not cell differentiation or regeneration is the major driving force of tissue repair. Additionally, ethical and safety problems have limited the application of stem cell therapies. Therefore, nonliving cell-derived techniques such as extracellular vesicle (EV) therapy and cell membrane-based therapy to fulfil the unmet demand for tissue repair are important. Nonliving cell-derived biomaterials are safer and more controllable, and their efficacy is easier to enhance through bioengineering approaches. Here, we described the development and evolution from cell therapy to EV therapy and cell membrane-based therapy for tissue repair. Furthermore, the latest advances in nonliving cell-derived therapies empowered by advanced engineering techniques are emphatically reviewed, and their potential and challenges in the future are discussed.
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Materiales Biocompatibles , Membrana Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Vesículas Extracelulares , Medicina Regenerativa , Animales , Diferenciación Celular , Humanos , Ratones , Células Madre/citología , Células Madre/fisiología , Cicatrización de HeridasRESUMEN
To observe the effect of Xinfeng Capsules on rheumatoid arthritis (RA) B lymphocytes,inflammatory mediators,FAK/CAPN/PI3K pathway,in order to explore the mechanism of Xinfeng Capsules in improving clinical symptoms of RA.Joint and systemic symptoms of RA patients were observed,and laboratory indicators[hemoglobin (HGB),platelet count (PLT),erythrocyte sedimentation (ESR),immunoglobulin (Ig) G,Ig A,Ig M,rheumatoid factor (RF),anti-cyclic citrulline antibody (CCP-AB),C-reactive protein (CRP)]were detected.ELISA was used to detect serum interleukin (IL)-1ßï¼IL-10,IL-33,chemokine 5 (CCL5),and vascular endothelial growth factor (VEGF).CD3~-CD19~+B cells were measured by flow cytometry.Western blot was used to detect FAK,p-FAK,CAPN,PI3K protein.The results showed that Xinfeng Capsules could significantly alleviate RA joint and systemic symptoms and improve clinical efficacy.And Xinfeng Capsules could increase HGB,decrease PLT,CCP-AB,CRP,ESR index,upregulate IL-10 expression,and down-regulate IL-1ßï¼IL-33,CCL5,VEGF,CD3~-CD19~+B cells,FAK,p-FAK,CAPN,PI3K expressions (P<0.01).Based on the above results,Xinfeng Capsules may reduce the expression of CD3~-CD19~+,regulate the balance of inflammatory cytokines and chemokines,inhibit abnormal activation of FAK/CAPN/PI3K pathway,and improve clinical symptoms of RA.
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Artritis Reumatoide , Fosfatidilinositol 3-Quinasas , Artritis Reumatoide/tratamiento farmacológico , Linfocitos B , Cápsulas , Medicamentos Herbarios Chinos , Humanos , Factor A de Crecimiento Endotelial VascularRESUMEN
A direct and selective synthesis of α,ß-unsaturated piperidones by a new palladium-catalyzed cascade carbonylation is described. In the presented protocol, easily available propargylic alcohols react with aliphatic amines to provide a broad variety of interesting heterocycles. Key to the success of this transformation is a remarkable catalytic cleavage of the present carbon-carbon triple bond by using a specific catalyst with 2-diphenylphosphinopyridine as ligand and appropriate reaction conditions. Mechanistic studies and control experiments revealed branched unsaturated acid 11 as crucial intermediate.
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The dicarbonylation of 1,3-butadiene to adipic acid derivatives offers the potential for a more cost-efficient and environmentally benign industrial process. However, the complex reaction network of regioisomeric carbonylation and isomerization pathways, make a selective and direct transformation particularly difficult. Here, we report surprising solvent effects on this palladium-catalysed process in the presence of 1,2-bis-di-tert-butylphosphin-oxylene (dtbpx) ligands, which allow adipate diester formation from 1,3-butadiene, carbon monoxide, and methanol with 97 % selectivity and 100 % atom-economy under scalable conditions. Under optimal conditions a variety of di- and triesters from 1,2- and 1,3-dienes can be obtained in good to excellent yields.
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Enantioselective hydrogenation of a broad spectrum of N-, O-, and S-containing aromatic benzoheterocycles or nonaromatic unsaturated heterocycles has been realized by using an Ir/SpinPHOX (SpinPHOX=spiro[4,4]-1,6-nonadiene-based phosphine-oxazoline) complex as the catalyst, affording an array of the corresponding chiral benzoheterocycles (30â examples) with excellent enantioselectivities (>99 %â ee in most cases) and turnover numbers up to 500.
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Laser engraving technology is a type of laser processing technology, widely used for product coding, marking, and so on. A large amount of research has reported the results of metal surface engraving; however, few research results, to the best of our knowledge, have provided theoretical support for the application of paper packaging laser engraving. In this paper, the quality of paper laser engraving is investigated by experimental methods. First, various phenomena appearing in paper carving were studied, including plant fiber burning, charcoal, and edge marks; second, the main factors affecting the quality of laser engraving are researched, and the influence of laser intensity and the preset width of carving marks on the engraving quality are discussed. The results show that the engraving precision is the best when the laser power is 11 W and the preset width is small (0.26 mm). Finally, the laser engraving precision of UV coated paper is studied, and the effect of UV material melting and secondary crystallization on engraving the quality of paper laser engraving quality is discussed. When the laser power is small, the maximum and minimum values of UV film melting and secondary crystallization engraving trace are relatively small as well; further, when the laser power increases, the maximum width of engraving is basically consistent with the preset width, and the precision of laser engraving is optimal.
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The first general and regioselective Pd-catalyzed cyclocarbonylation to give α-methylene-ß-lactones is reported. Key to the success for this process is the use of a specific sterically demanding phosphine ligand based on N-arylated imidazole (L11) in the presence of Pd(MeCN)2 Cl2 as pre-catalyst. A variety of easily available alkynols provide under additive-free conditions the corresponding α-methylene-ß-lactones in moderate to good yields with excellent regio- and diastereoselectivity. The applicability of this novel methodology is showcased by the direct carbonylation of biologically active molecules including natural products.
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Lactonas/química , Lactonas/síntesis química , Paladio/química , Catálisis , Ciclización , Ligandos , Estructura MolecularRESUMEN
A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium-catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity.
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TCEA3 is a member of the transcription elongation factor family that not only promotes transcription but may also participate in other cytoplasmic processes. However, its mechanisms of action remain unclear. Our previous study indicated that TCEA3 may affect muscle differentiation. In this study, we investigated the expression and localization of TCEA3 in C2C12 cells and examined the role of TCEA3 in differentiation, its interaction with other cell proteins, and mechanisms of action. We found that the expression of TCEA3 increased gradually with an increase in the number of differentiation days and that it is mainly expressed in the cytoplasm of C2C12 cells, of which it promotes differentiation. Coimmunoprecipitation experiments and western blot analysis revealed that TCEA3 interacts with Annexin A1 (ANXA1), which is located in the cytoplasm and also promotes cell differentiation. Collectively, our results indicate that TCEA3 promotes cell differentiation by interacting with ANXA1 and affecting transforming growth factor-ß signaling pathways.