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Herein, a electroreductive carboxylation of benzylphosphonium salts was achieved by the cleavage of the C(sp3)-P bond, and various valuable arylacetic acids could be synthesized by this strategy. Also, based on control experiments and previous studies, a plausible reaction mechanism was proposed to explain the reaction process. The establishment of this procedure will provide a new paradigm for the functionalization of alkyl phosphonium salts.
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Herein, electroreductive umpolung benzylic deuteration of p-QMs using cheap and easily accessible D2O as a deuterium source is reported. Various value-added benzylic deuterated diarylmethanes can be synthesized without the requirement of noble metal catalysts, redox reagents, and strong bases. The establishment of this protocol will provide an alternative strategy for acquiring benzylic deuterated diarylmethanes.
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The qnrE family was designated in 2017. To date, two qnrE alleles have been discovered that are carried by plasmids. Here, we identified a new quinolone resistance gene, qnrE3, in the chromosome of Enterobacter mori clinical isolate 08-091 in China. qnrE3 conferred decreased susceptibility to fluoroquinolones, similar to qnrE1 and qnrE2. To investigate the precise origin of qnrE1, qnrE2, and qnrE3, 79 qnrE-bearing strains producing 30 qnrE variants were retrieved from the NCBI database. Phylogenetic analysis illustrated two major clusters, QnrEEmo and QnrEEas, produced mainly by the E. mori and E. asburiae strains, respectively. Comparison of the genetic context of qnrE alleles demonstrated that qnrE3 and qnrEEas2 alleles presumably were captured by ISEcp1 and mobilized from the E. mori and E. asburiae strains to the E. xiangfangensis and Escherichia coli strains, respectively. qnrEEas2 was proposed to be named qnrE4, since it has spread to another genus. All the qnrE alleles were harbored by the Enterobacter species, except those captured by ISEcp1 and mobilized into other species of Enterobacterales. E. mori is probably the source of qnrE1 to qnrE3 alleles, and E. asburiae is the reservoir of qnrE4.
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Quinolonas , Antibacterianos/farmacología , Enterobacter/genética , Enterobacter cloacae , Humanos , Pruebas de Sensibilidad Microbiana , Filogenia , Quinolonas/farmacologíaRESUMEN
Here, we report a novel narrow-spectrum ß-lactamase CTX-M-215 identified in an Escherichia coli clinical isolate in China and conferring high-level resistance to mecillinam but not to cefotaxime. CTX-M-215 differed from CTX-M-125, a CTX-M extended-spectrum ß-lactamase (ESBL), by an N132D substitution, which decreased hydrolytic activities toward penicillins and cephalosporins except for mecillinam. High similarity was observed between CTX-M-215- and CTX-M-125-bearing plasmids, carried by different isolates in the same patient, indicating in vivo evolution of CTX-M-215 from CTX-M-125.
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Infecciones por Escherichia coli , beta-Lactamasas , Amdinocilina , Antibacterianos/farmacología , China , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Humanos , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , beta-Lactamasas/genéticaRESUMEN
OBJECTIVES: Imipenem-relebactam (IMR), a novel ß-lactam/ß-lactamase inhibitor combination, is recommended for infections caused by difficult-to-treat Pseudomonas aeruginosa. This study aimed to investigate the evolution trajectory of IMR resistance under the selection of levofloxacin in P. aeruginosa. METHODS: Antimicrobial susceptibility testing, complete genome sequencing and gene manipulation experiments were performed. Quantitative reverse transcription PCR for specific genes and porin levels were detected. Evolution trajectory was simulated in vitro by induction assay. RESULTS: P. aeruginosa HS347 and HS355 were isolated from abdominal drainage of two neighbouring patients (S and Z) undergoing surgery of colon carcinoma in Shanghai, China, with the latter patient having received levofloxacin. They were closely related ST16 strains, and both carried blaKPC-2 plasmids highly similar to those of P. aeruginosa endemic clones from Zhejiang province, where patient Z had received enteroscopy before this admission. Acquisition of resistance was observed for both IMR and fluoroquinolones in HS355, likely prompted by treatment with levofloxacin. The T274I substitution in MexS (putative oxidoreductase), upregulated efflux pump operon mexEF-oprN and decreased production of porin OprD leading to cross-resistance to fluoroquinolones and IMR, which was also verified by in vitro mutant selection under levofloxacin selection. CONCLUSIONS: The emergence of a rare blaKPC-2-plasmid-bearing ST16 clone implies the horizonal spread and inter-regional dissemination of a high-risk plasmid-clone combination, representing a public health challenge. Levofloxacin exposure can select for mexS inactivating mutation, which in turn leads to IMR resistance phenotype, implicating the role of an unrelated, widely used antimicrobial agent in insidiously triggering the development of cross resistance to a latest ß-lactam/ß-lactamase inhibitor combination.
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Antibacterianos , Compuestos de Azabiciclo , Imipenem , Levofloxacino , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas , Pseudomonas aeruginosa , beta-Lactamasas , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Levofloxacino/farmacología , Humanos , Compuestos de Azabiciclo/farmacología , Imipenem/farmacología , beta-Lactamasas/genética , Antibacterianos/farmacología , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/tratamiento farmacológico , China , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Mutación , Inhibidores de beta-Lactamasas/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Plásmidos/genéticaRESUMEN
Internet gaming disorder (IGD) is significantly associated with depression across previous studies, and significantly affects the development of mental health among Chinese adolescents. In this two-wave longitudinal research, we tested the mediating role of maladaptive cognition and the moderating role of mindfulness in the linkage between depression and IGD among Chinese adolescents (N = 580, 355 females, average age = 15.76 years, SD = 1.31) who completed questionnaires. Results of regression-based analyses showed that depression was positively related to IGD. Maladaptive cognition significantly mediated the link between depression and IGD. Moreover, mindfulness moderated the second part of the mediation process. Specifically, as the level of mindfulness increased, the influence of depression on the future IGD through maladaptive cognition was weakened. The present study demonstrates the key roles of maladaptive cognition and mindfulness in the link between depression and IGD, and further supports the cognitive-behavioral model of pathological Internet use.
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Conducta Adictiva , Juegos de Video , Femenino , Humanos , Adolescente , Depresión , Trastorno de Adicción a Internet , Pueblos del Este de Asia , Conducta Adictiva/psicología , Juegos de Video/psicología , InternetRESUMEN
The association between excessive screen media use and mental health problems has attracted widespread attention. The literature to date has neglected the biological mechanisms underlying such a relationship and failed to distinguish between different types of screen media activities. A sample from the Adolescent Brain and Cognitive Development study was used in the present study to elucidate the longitudinal associations between specific types of screen media use, brain development, and diverse mental health problems. The results showed that different types of screen media use have differentiated associations with mental health problems, subcortical volume, and cortical-subcortical connectivity. Specifically, more passive media use was associated with increased rule-breaking behavior, while more video game playing was associated with increased withdrawn/depressed symptoms. In addition, more social media use was associated with a reduced volume of the hippocampus, caudate, and thalamus proper. More research is needed to examine the differential effects of screen media use on neurodevelopmental processes and mental health problems across adolescence.
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Introduction: Parenting and peer victimization (PV) are crucial for adolescent drinking. To further explore the cause of adolescent drinking, the present study investigated the role of PV and personal growth initiative (PGI) in the relationship between parental corporal punishment (PCP) and adolescent drinking. Methods: Present study build moderated mediation models to test the hypothesis, and detailed analysis of gender differences was conducted on the models. The data were collected in a cross-sectional questionnaire study with n = 1,007 adolescents (mean age = 13.16 years, 51.84% girls, n = 522). Results: Model analysis showed that: (1) PV totally mediated the relationship between PCP and adolescent girls' drinking behavior; (2) The positive association between PV and drinking was only significant for girls with low PGI. Discussion: These findings underscore the importance of the protective effect of a personality trait characterized by spontaneous self-promotion on adolescent girls' drinking.
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In this work, a PCN/Fe2O3/CdS ternary heterojuction photocatalyst was constructed by introducing an appropriate amount of ferric oxide (Fe2O3) and cadmium sulfide (CdS) onto porous carbon nitride (PCN), denoted as PCN/Fe2O3/CdS. In the presence of PCN/Fe2O3/CdS, the turnover frequency value and selectivity of the oxidative coupling reaction of benzylamine were 6740 µmol g-1 h-1 and 99.4%, respectively. The excellent catalytic performance of the PCN/Fe2O3/CdS photocatalyst is attributed to fully exposed active sites due to the porous structure of PCN, improved light utilization efficiency by introduction of Fe2O3 and CdS, and increased mobility of e--h+ pairs by construction of a ternary heterostructure, and was proved by the analysis of its structural and optical properties. According to the substrate scope study and Hammett diagram analysis, the rate determining step of the benzylamine self-coupling reaction photocatalyzed by PCN/Fe2O3/CdS was the condensation of imine and benzylamine into N-benzylidenebenzylamine. The results of the free radical quenching experiment and electron spin resonance tests showed that h+ played a major role in the photoreaction process, followed by ËO2- and ËOH. After four photocatalytic reaction cycles, the catalytic performance of the PCN/Fe2O3/CdS heterojunction composite material remained good. Finally, combined with the free radical trapping experiment and energy band structure analysis, a possible double Z-type reaction mechanism was proposed.
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We first report an efficient combined strategy that simultaneously integrates copolymerization, doping, and molecular self-assembly for the development of carbon-doping petal-like carbon nitride photocatalysts using melamine (MA), cyanuric acid (CA), and 2,4,6-triaminopyrimidine (TAP) as the starting precursors and water as the only green solvent. The morphology, textural, optical, and electronic properties of carbon nitride could be engineered by rationally manipulating the doping content of TAP. In the process of molecular self-assembly, TAP can insert the aggregate edge easily according to the results of density functional theory (DFT) calculations. The edge-termination effect of TAP made it easier for the modified carbon nitride materials to form petal-like nanosheets with porous structures and large BET surface areas. In addition, the incorporation of TAP also contributed to tuning the electronic band structures of carbon nitrides and enhancing the separation efficiency of photogenerated carriers. The as-prepared materials exhibited excellent photocatalytic activities in the degradation of tetracycline hydrochloride (TC-HCl) and rhodamine B (RhB). This work may not only offer universally powerful and stable photocatalysts for applications but also develop a new combined strategy to fabricate efficient photocatalysts in a facile and green way.
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Environmental remediation based on semiconducting materials offers a green solution for pollution control in water. Herein, we report a novel graphitic carbon nitride (g-C3N4) by one-step polycondensation of urea. The novel g-C3N4 material with a surface area of 114 m2 g-1 allowed the repetitive adsorption of the rhodamine B (RhB) dye and facilitated its complete photocatalytic degradation upon light irradiation in 20 min. This study provides new insights into the fabrication of g-C3N4-based materials and facilitates their potential application in the synergistic removal of harmful organic pollutants in the field of water purification.