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1.
Angew Chem Int Ed Engl ; : e202411382, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39405000

RESUMO

High-affinity, specific, and sensitive probes are crucial for the specific recognition and identification of tumor cells from complex matrices. Multivalent binding is a powerful strategy, but the irrational spatial distribution of the functional moieties may reduce the probe performance. Here, we constructed a Janus DNA triangular prism nanostructure (3Zy1-JTP-3) for sensitive detection and specific isolation of tumor cells. Benefiting from spatial features of the triangular prism, the fluorescence intensity induced by 3Zy1-JTP-3 was almost 4 times that of the monovalent structure. Moreover, the DNA triangular prisms were connected to form hand-in-hand multivalent DNA triangular prism structures (Zy1-MTP), in which the fluorescence intensity and affinity were increased to 9-fold and 10-fold of 3Zy1-JTP-3, respectively. Furthermore, 3Zy1-JTP-3 and Zy1-MTP were combined with magnetic beads, and the latter showed higher capture efficiency (> 90%) in whole blood. This work provides a new strategy for the efficient capture of rare cells in complex biological samples.

2.
Front Psychol ; 15: 1408396, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39291173

RESUMO

Background: Non-suicidal self-injury (NSSI) is a worldwide mental health problem that deserves thorough investigation. This study aims to explore the effect of parenting styles, attachment to parents, and self-compassion on the occurrence of non-suicidal self-injury (NSSI) behavior in adolescents and whether these factors influence their recovery motivation. Methods: A total of 132 adolescents who had engaged in NSSI within the last year and 72 adolescents who had never engaged in NSSI were recruited from the Shenzhen Kangning Hospital and from primary and secondary schools and communities. Differences in the Hamilton Depression Scale (HAMD), Inventory of Parent and Peer Attachment (IPPA), Egma Minn av. Bardndosnauppforstran (EMBU), and Self-Compassion Scale (SCS) of participants were compared. A binary logistic model was established to measure the odds ratios of these variables on the occurrence of NSSI. In the NSSI adolescent sample, separate binary logistic models were created with NSSI impulse inhibition, NSSI resistance activity, and NSSI recovery motivation as dependent variables and with parenting styles, attachment to parents, and self-compassion as independent variables. Results: Compared with adolescents with no NSSI behavior, those who had engaged in NSSI within the past year had higher scores on the HAMD, as well as higher EMBU-negative father parental behavior (punishment, excessive interference, rejection, and overprotection), EMBU-negative mother parental behavior (excessive interference, rejection, and punishment), and SCS negative self-compassion scores. Moreover, adolescents with NSSI had lower EMBU-father emotional warmth, EMBU-mother emotional warmth, IPPA-attachment to father, IPPA-attachment to mother, and SCS positive self-compassion scores. Current depressive symptoms and maternal punishment are risk factors for NSSI in adolescents, while positive self-compassion was a protective factor. Positive self-compassion can positively predict NSSI impulse inhibition, NSSI resistance activity, and NSSI recovery motivation. However, we unexpectedly found that the father's emotional warmth negatively predicts NSSI resistance activity. Conclusion: This study found that positive self-compassion has a significant impact on the prevention of and recovery from NSSI behavior in adolescents.

3.
Plant Physiol Biochem ; 216: 109092, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39241626

RESUMO

Continuous cropping of peanuts presents significant challenges to sustainable production due to soil-borne diseases like root rot caused by Fusarium species. In this study, field inoculation experiments treatments and in vitro agar plate confrontation tests were conducted, including non-inoculated controls (CK), inoculation with Pseudomonas fluorescens (PF), Fusarium oxysporum (FO), and co-inoculation with both (PF + FO). The aim was to explore the antifungal mechanisms of Pseudomonas fluorescens in mitigating root rot and enhancing peanut yield. The results indicated that PF and PF + FO significantly enhanced peanut root activity, as well as superoxide dismutase, catalase, and glutathione S-transferase activities, while simultaneously decreasing the accumulation of reactive oxygen species and malondialdehyde contents, compared to FO treatment. Additionally, PF treatment notably increased lignin content through enhanced phenylalanine ammonia lyase, cinnamate 3-hydroxylase, and peroxidase activity compared to CK and FO treatment. Moreover, PF treatment resulted in longer roots and a higher average diameter and surface area, potentially due to increased endogenous levels of auxin and zeatin riboside, coupled with decreased abscisic acid content. PF treatment significantly elevated chlorophyll content and the maximum photochemical efficiency of PSII in the light-adapted state, the actual photochemical efficiency and the proportion of PSII reaction centers open, leading to improved photosynthetic performance. Confrontation culture assays revealed PF's notable inhibitory effects on Fusarium oxysporum growth, subsequently reducing rot disease incidence in the field. Ultimately, PF treatment led to increased peanut yield by enhancing plant numbers and pod weight compared to FO treatment, indicating its potential in mitigating Fusarium oxysporum-induced root rot disease under continuous cropping systems.

4.
J Chem Phys ; 161(12)2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39319660

RESUMO

As a precursor to various reactive nitrogen species formed in biological systems, nitric oxide (•NO) participates in numerous processes, including enhancing DNA radiosensitivity in ionizing radiation-based radiotherapy. Forming guanine radical cations is another common DNA lesion resulting from ionization and oxidation damage. As such, the interaction of •NO with guanine radical cations (G•+) may contribute to the radiosensitization of •NO. An intriguing aspect of this process is the participation of multiple spin configurations in the reaction, including open-shell singlet 1,OS[G•+(↑)⋯(↓)•NO], closed-shell singlet 1,CS[G(↑↓)⋯NO+], and triplet 3[G•+(↑)⋯(↑)•NO]. In this study, the reactions of •NO with both unsubstituted guanine radical cations (in the 9HG•+ conformation) and 9-methylguanine radical cations (9MG•+, a guanosine-mimicking model compound) were investigated in the absence and presence of monohydration of radical cations. Kinetic-energy dependent reaction product ions and cross sections were measured using an electrospray ionization guided-ion beam tandem mass spectrometer. The reaction mechanisms, kinetics, and dynamics were comprehended by interpreting the reaction potential energy surface using spin-projected density functional theory, coupled cluster theory, and multiconfiguration complete active space second-order perturbation theory, followed by RRKM kinetics modeling. The combined experimental and computational findings revealed closed-shell singlet 1,CS[7-NO-9MG]+ as the major, exothermic product and triplet 3[8-NO-9MG]+ as the minor, endothermic product. Singlet biradical products were not detected due to high reaction endothermicities, activation barriers, and inherent instability.


Assuntos
Cátions , Elétrons , Guanina , Óxido Nítrico , Guanina/química , Guanina/análogos & derivados , Óxido Nítrico/química , Cinética , Radicais Livres/química , Cátions/química , Teoria da Densidade Funcional
5.
Talanta ; 280: 126701, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142129

RESUMO

Point-of-care testing of multiple chronic disease biomarkers is crucial for timely intervention and management of chronic diseases. Here, a "sample-to-answer" microfluidic chip was developed for simultaneous detection of multiple chronic disease biomarkers in whole blood by integrating a plasma separation module. The whole detection process is very convenient, i.e., just add whole blood and get the results. The chip successfully achieved the simultaneous detection of total cholesterol, triglycerides, uric acid, and glucose in undiluted whole blood within 21 min, including 6 min for plasma separation and 15 min for enzymatic chromogenic reactions. Moreover, the sensitivity levels of on-chip detection of chronic disease biomarkers can also meet clinically relevant thresholds. The chip is easy to use and has significant potential to improve home self-management of chronic diseases and enhance healthcare outcomes.


Assuntos
Biomarcadores , Dispositivos Lab-On-A-Chip , Triglicerídeos , Humanos , Biomarcadores/sangue , Doença Crônica , Triglicerídeos/sangue , Colesterol/sangue , Ácido Úrico/sangue , Glicemia/análise , Técnicas Analíticas Microfluídicas/instrumentação , Plasma/química
6.
Phys Chem Chem Phys ; 26(32): 21697-21711, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092620

RESUMO

The formation and fragmentation of negatively charged 2-hydroxyethylhydrazinium nitrate ([HOCH2CH2NH2NH2]+NO3-, HEHN) ionic liquid clusters were examined using a guided-ion beam tandem mass spectrometer furnished with collision-induced dissociation of selected ions with Xe atoms. Measurements included the compositions of cluster ions formed in the ionization source, and the dissociation products, cross sections, and 0 K threshold energies for individually selected cluster ions. To identify the structures of the main cluster ion series [(HEHN)n(HNO3)0-1NO3]- formed, molecular dynamics simulations were employed to create initial geometry guesses, followed by optimization at the ωB97XD/6-31+G(d,p) level of theory, from which global minimum structures were identified for reaction thermodynamics analyses. A comparison was made between the cluster formation and fragmentation in the negatively charged 2-hydroxyethylhydrazinium nitrate with those in the positive mode (reported by W. Zhou et al., Phys. Chem. Chem. Phys., 2023, 25, 17370). In both modes, the cluster ions were predominantly composed of m/z below 350; loss of a neutral 2-hydroxyethylhydrazinium nitrate ion pair represents the most important cluster fragmentation pathway, followed by intra-ion pair proton transfer-mediated 2-hydroxyethylhydrazine and HNO3 elimination; and all clusters started to dissociate at threshold energies less than 1.5 eV. The overwhelming similarities in the formation and fragmentation chemistry of positively vs. negatively charged 2-hydroxyethylhydrazinium nitrate clusters may be attributed to their inherent ionic nature and high electric conductivities.

7.
Adv Healthc Mater ; : e2402023, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092635

RESUMO

Transmembrane ion transport modality has received a widespread attention due to its apoptotic activation toward anticancer cell activities. In this study, G-quadruplex-based potassium-specific transmembrane channels have been developed to facilitate the intracellular K+ efflux, which perturbs the cellular ion homeostasis thereby inducing cancer cell apoptosis. Cholesterol-tag, a lipophilic anchor moiety, serves as a rudiment for the G-quadruplex immobilization onto the membrane, while G-quadruplex channel structure as a transport module permits ion binding and migration along the channels. A c-Myc sequence tagged with two-cholesterol is designed as a representative lipophilic G-quadruplex, which forms intramolecular parallel G-quadruplex with three stacks of G-quartets (Ch2-Para3). Fluorescence transport assay demonstrates Ch2-Para3 a high transport activity (EC50 = 10.9 × 10-6 m) and an ion selectivity (K+/Na+ selectivity ratio of 84). Ch2-Para3 mediated K+ efflux in cancer cells is revealed to purge cancer cells through K+ efflux-mediated cell apoptosis, which is confirmed by monitoring the changes in membrane potential of mitochondria, leakage of cytochrome c, reactive oxygen species yield, as well as activation of a family of caspases. The lipophilic G-quadruplex exhibits obvious antitumor activity in vivo without systemic toxicity. This study provides a functional scheme aimed at generating DNA-based selective artificial membrane channels for the purpose of regulating cellular processes and inducing cell apoptosis, which shows a great promising for anticancer therapy in the future.

8.
Chem Sci ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39149221

RESUMO

In nature, biochemical processes depend on polymorphism, a phenomenon by which discrete biomolecules can adopt specific conformations based on their environment. However, it is often difficult to explore the generation mechanism and achieve polymorphic control in artificial supramolecular assembly systems. In this work, we propose a feasible thought for exploring the transformation mechanism of polymorphism in peptide assembly from the perspective of thermodynamic regulation, which enables polymorphic composition to be limited by switchable intramolecular CH⋯π attraction within a certain temperature range. Combined with the density functional theory calculations, we obtained thermodynamic theoretical data supporting the conformation transition and the underlying polymorphism formation principle. Afterward, we properly designed the peptide to alter the probability of CH⋯π attraction occurring. Then, we selectively obtained a homogeneous morphological form with corresponding molecular conformation, which further demonstrated the important role of molecular conformational manipulation in polymorphism selection. This unique template-based strategy developed in this study may provide scientists with an additional line of thought to guide assembly paths in other polymorphic systems.

9.
Int Immunopharmacol ; 140: 112756, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39083932

RESUMO

BACKGROUND: Altered expression and activity of solute carrier family 4 member 4 (SLC4A4) could affect the growth, survival and metastasis of tumor cells. Currently, the role of SLC4A4 in lung adenocarcinoma (LUAD) immunotherapy and prognosis was not entirely clear. METHODS: We analyzed SLC4A4 expression in LUAD tissues and cell lines using quantitative reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemistry. The effects of SLC4A4 overexpression on angiogenesis, cell migration, invasion, and epithelial-mesenchymal transition were examined. Public databases helped construct a risk model evaluating SLC4A4's expression on LUAD prognosis and immunotherapy response. Additionally, a xenograft model, flow cytometry, and enzyme-linked immunosorbent assay further explored SLC4A4's role in tumor immune microenvironment infiltration. RESULTS: Upregulation of SLC4A4 promoted apoptosis in the LUAD cell line and significantly inhibited the migration and invasive ability of cancer cells (P<0.01). A total of 10 key genes (including SIGLEC6, RHOV, PIR, MOB3B, MIR3135B, LPAR6, KRT8, ITGA2, CPS1, and C6) were screened according to SLC4A4 expression, immune score and stromal score, and a prognostic model with good outcome was constructed (AUC values of which in the training cohort at 1,3, and 5 years reached 0.73, 0.73, and 0.72, respectively). Importantly, we demonstrated that high expression of SLC4A4 was able to increase the proliferation level and cytokine secretion of CD8+ T cells for the purpose of promoting the immune system response to LUAD. CONCLUSION: Our study revealed that SLC4A4 can serve as a prognostic indicator for LUAD, providing new insights into the treatment and diagnosis of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Biomarcadores Tumorais , Movimento Celular , Neoplasias Pulmonares , Microambiente Tumoral , Humanos , Animais , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/mortalidade , Linhagem Celular Tumoral , Camundongos , Microambiente Tumoral/imunologia , Prognóstico , Regulação Neoplásica da Expressão Gênica , Transição Epitelial-Mesenquimal , Feminino , Camundongos Nus , Masculino , Progressão da Doença , Apoptose , Ensaios Antitumorais Modelo de Xenoenxerto
10.
European J Org Chem ; 27(23)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-39051029

RESUMO

n-Bu4NI/K2S2O8 mediated C-N coupling between aldehydes and amides is reported. A strong electronic effect is observed on the aromatic aldehyde substrates. The transformylation from aldehyde to amide takes place exclusively when an aromatic aldehyde bears electron-donating groups at either the ortho or para position of the formyl group, while the cross-dehydrogenative coupling dominates in the absence of these groups. Both the density functional theory (DFT) thermochemistry calculations and experimental data support the proposed single electron transfer mechanism with the formation of an acyl radical intermediate in the cross-dehydrogenative coupling. The n-Bu4NI/K2S2O8 mediated oxidative cyclization between 2-aminobenzamide and aldehydes is also reported, with four quinazolin-4(3H)-ones prepared in 65-99% yields.

11.
Adv Biol (Weinh) ; : e2400242, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037400

RESUMO

Erythrocytes, also known as red blood cells (RBCs), have garnered considerable attention as potential carriers for drug delivery, owing to their inherent properties such as biocompatibility, biodegradability, and prolonged circulation half-life. This paper presents a comprehensive overview of the role of erythrocytes in drug delivery, elucidating recent advancements in delivering a diverse array of therapeutic agents, including small molecules, nucleic acids, antibodies, protein enzymes, and nanoparticles. Two primary strategies for encapsulating drugs within erythrocytes are systematically discussed: internal loading and surface loading. Each strategy offers distinct advantages in terms of drug stability and release kinetics. Notably, the utilization of erythrocyte membrane camouflaged nanocarriers holds promise for enhancing the biocompatibility of conventional nanoparticles and facilitating targeted drug delivery. Furthermore, the broad spectrum of biomedical applications of erythrocyte-based drug delivery systems are examined, ranging from cancer treatment to diabetes management, thrombosis prevention, and immunotherapy. This review provides a comprehensive evaluation of current technologies in erythrocyte-loaded drug delivery, highlighting the strengths, weaknesses, and future directions for advancing therapeutic interventions in various disease contexts.

12.
Anal Chem ; 96(29): 11985-11996, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38989829

RESUMO

Accelerating the migration of interfacial carriers in heterojunctions is crucial for achieving highly sensitive photoelectrochemical (PEC) sensing. In this study, we developed three-dimensional (3D)/two-dimensional (2D) CuInS2/red phosphorus nanosheet (CuInS2/RP NS) n-n heterojunction functional materials with enhanced interfacial charge transfer capabilities for PEC sensing. The 3D CuInS2 serves as a conductive layer, providing excellent electronic conductivity and superior electron absorption and transport properties. In contrast, the ultrathin RP NS acts as a transport layer that enhances carrier mobility. The 3D/2D heterojunction ensures a large interface contact surface, shortening the carrier transport distance. A well-aligned band position generates a substantial built-in electric field, providing a significant driving force for efficient carrier separation and migration, thereby improving response sensitivity. A PEC aptamer sensor was constructed based on the synthesized heterostructure for ciprofloxacin detection. The detection limit of the CuInS2/RP NS aptamer sensor for ciprofloxacin is 2.03 × 10-15 mg·mL-1, with a linear range from 1.0 × 10-14 to 1.0 × 10-5 mg·mL-1. This work presents a strategy for enhancing the photoelectric response by modulating the interface structure of heterojunctions, thereby opening new prospects for the application of highly sensitive PEC sensors in antibiotic detection.

13.
Medicine (Baltimore) ; 103(30): e39063, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058881

RESUMO

BACKGROUND: Remimazolam, a recently developed anesthetic characterized by its rapid and ultra-short-acting properties, exhibits pharmacological attributes that make it potentially suitable for painless surgical abortion procedures. The objective of this study was to determine the effective dose of remimazolam when administered in combination with sufentanil, with the intention of inhibiting body movement during surgical abortion. Additionally, a secondary objective was to assess the recovery profile from general anesthesia. METHODS: The study enrolled a total of 25 healthy women aged 20 to 40, with a body mass index between 18 and 28 kg/m2, in their first trimester of pregnancy (up to 12 weeks), and American Society of Anesthesiologists status I and II. Anesthesia induction was initiated by administering sufentanil at a dose of 0.1 µg/kg. The modified Dixon up-and-down method was employed to determine the induction dose of remimazolam for each patient. RESULTS: The 50% and 95% effective dose of remimazolam for inhibitory effects of body movement was estimated using centered isotonic regression to be 0.145 mg/kg (95% CI: 0.115, 0.207), and 0.242 mg/kg (95% CI: 0.232, 0.620), respectively. Five out of 25 (20%) experienced hiccups, with 1 patient having persistent hiccups until the end of the surgery. The mean time to first eye-opening was 51.4 ±â€…20.5 seconds, and the time to obey verbal command was 54.5 ±â€…20.6 seconds. Upon arrival at the postanesthesia care unit, 95.7% of the patients achieved a Modified Aldrete score ≥ 9. CONCLUSIONS: The 50% and 95% effective dose of remimazolam for inhibiting body movement during surgical abortion when used in combination with 0.1 µg/kg of sufentanil were 0.145 mg/kg and 0.242 mg/kg, respectively.


Assuntos
Aborto Induzido , Sufentanil , Humanos , Feminino , Adulto , Sufentanil/administração & dosagem , Aborto Induzido/métodos , Gravidez , Adulto Jovem , Benzodiazepinas/administração & dosagem , Movimento/efeitos dos fármacos , Relação Dose-Resposta a Droga , Período de Recuperação da Anestesia , Anestesia Geral/métodos , Hipnóticos e Sedativos/administração & dosagem
14.
J Affect Disord ; 363: 436-444, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39029701

RESUMO

BACKGROUND: Childhood Emotional Abuse (CEA) is a known risk factor for Non Suicidal Self-injury (NSSI), which could have devastating repercussions. This study aimed to establish whether Parent-Child Attachment (PCA) and depressive symptoms mediated the CEA-NSSI relationship, as well as whether school connectedness moderated both the direct and indirect relationships between CEA and NSSI. METHODS: Between November and December 2022, 7447 Chinese adolescents in high schools were surveyed through multi-stage cluster random sampling. The participants completed self-reported questionnaires that assessed CEA, PCA, depressive symptoms, school connectedness, and NSSI. Relationships between these variables were examined through moderated mediation analysis using SPSS macro-PROCESS. RESULTS: After controlling for sociodemographic variables, we found that CEA correlated positively with NSSI through two different pathways: the mediating role of depressive symptoms and the chain-mediating role of both PCA and depressive symptoms. Moreover, school connectedness could moderate the direct and indirect relationships between CEA and NSSI. LIMITATIONS: The study's cross-sectional design does not allow for causal inferences. CONCLUSIONS: Overall, PCA, depressive symptoms, and school connectedness could affect the CEA-NSSI relationship.


Assuntos
Depressão , Comportamento Autodestrutivo , Humanos , Feminino , Masculino , China/epidemiologia , Adolescente , Comportamento Autodestrutivo/psicologia , Comportamento Autodestrutivo/epidemiologia , Depressão/psicologia , Depressão/epidemiologia , Estudos Transversais , Relações Pais-Filho , Análise de Mediação , Abuso Emocional/psicologia , Abuso Emocional/estatística & dados numéricos , Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/estatística & dados numéricos , Fatores de Risco , Inquéritos e Questionários , Criança , Instituições Acadêmicas , Autorrelato
15.
Fitoterapia ; 177: 106048, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38838825

RESUMO

Four new phenols and one new aminobenzoic acid derivative, with five known phenols were isolated from the roots of Rhus chinensis Mill. Their structures were elucidated by UV, IR, HRESIMS, 1D and 2D NMR spectra, as well as optical rotations. Compound 4 significantly inhibited mouse ear inflammation (inhibitory rate of 44.03%), and significantly extended the time of pain response (extension rate of 48.55%), showing significant anti-inflammatory and analgesic effects in vivo.


Assuntos
Analgésicos , Anti-Inflamatórios , Fenóis , Raízes de Plantas , Rhus , Animais , Raízes de Plantas/química , Camundongos , Estrutura Molecular , Fenóis/isolamento & purificação , Fenóis/farmacologia , Fenóis/química , Rhus/química , Analgésicos/farmacologia , Analgésicos/isolamento & purificação , Analgésicos/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Masculino , Dor/tratamento farmacológico , Dor/induzido quimicamente , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Inflamação/tratamento farmacológico , China
16.
Adv Synth Catal ; 366(11): 2489-2494, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38895098

RESUMO

n-Bu4NI/K2S2O8 mediated transformylation from p-anisaldehyde to primary amides is reported. The mechanistic studies suggest the reaction occurs via a single electron transfer pathway. Based on the DFT electronic structure calculations of various reaction pathways, the most plausible mechanism involves the formation of a phenyl radical cation and an arenium ion as the key intermediates. It represents the first example where p-anisaldehyde is employed as a formyl source via a non-metal mediated Csp2-Csp2 bond cleavage.

17.
Nat Commun ; 15(1): 4196, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760357

RESUMO

Precious metals are core assets for the development of modern technologies in various fields. Their scarcity poses the question of their cost, life cycle and reuse. Recently, an emerging catalysis employing contact-electrification (CE) at water-solid interfaces to drive redox reaction, called contact-electro-catalysis (CEC), has been used to develop metal free mechano-catalytic methods to efficiently degrade refractory organic compounds, produce hydrogen peroxide, or leach metals from spent Li-Ion batteries. Here, we show ultrasonic CEC can successfully drive the reduction of Ag(ac), Rh3+, [PtCl4]2-, Ag+, Hg2+, Pd2+, [AuCl4]-, and Ir3+, in both anaerobic and aerobic conditions. The effect of oxygen on the reaction is studied by electron paramagnetic resonance (EPR) spectroscopy and ab-initio simulation. Combining measurements of charge transfers during water-solid CE, EPR spectroscopy and gold extraction experiments help show the link between CE and CEC. What's more, this method based on water-solid CE is capable of extracting gold from synthetic solutions with concentrations ranging from as low as 0.196 ppm up to 196 ppm, reaching in 3 h extraction capacities ranging from 0.756 to 722.5 mg g-1 in 3 h. Finally, we showed CEC is employed to design a metal-free, selective, and recyclable catalytic gold extraction methods from e-waste aqueous leachates.

18.
Psychol Res Behav Manag ; 17: 1819-1830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716259

RESUMO

Background: The present study aimed to investigate the potential role of perceived stress, impulsivity trait, executive dysfunction in non-suicidal self-injury (NSSI) thoughts among college students, as well as the gender differences. Methods: A sample of 890 university students completed self-report measures of NSSI thoughts in the past month, the level of perceived stress, impulsivity traits, and executive dysfunction. Results: Compared to those with low level of perceived stress, participants with high level of perceived stress reported significant higher levels of impulsivity trait and executive dysfunction, and higher frequency of NSSI thoughts, and there were no gender differences. Male participants with NSSI thoughts, compared to males without NSSI thoughts, reported significant higher levels of perceived stress and executive dysfunction. Female participants with NSSI thoughts, compared to females without NSSI thoughts, reported significant higher levels of perceived stress, impulsivity trait, and executive dysfunction. Hierarchical regression analysis revealed only executive dysfunction was associated with NSSI thoughts in males, while only perceived stress was associated with NSSI thoughts in females. Conclusion: This study revealed different influence factors for NSSI thoughts in male and female college students. NSSI thoughts in males were more likely associated with executive dysfunction while in females were due to recently perceived stress.

19.
Proc Natl Acad Sci U S A ; 121(15): e2321116121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557176

RESUMO

Multidrug resistance (MDR) is a major factor in the failure of many forms of tumor chemotherapy. Development of a specific ligand for MDR-reversal would enhance the intracellular accumulation of therapeutic agents and effectively improve the tumor treatments. Here, an aptamer was screened against a doxorubicin (DOX)-resistant human hepatocellular carcinoma cell line (HepG2/DOX) via cell-based systematic evolution of ligands by exponential enrichment. A 50 nt truncated sequence termed d3 was obtained with high affinity and specificity for HepG2/DOX cells. Multidrug resistance protein 1 (MDR1) is determined to be a possible recognition target of the selected aptamer. Aptamer d3 binding was revealed to block the MDR of the tumor cells and increase the accumulation of intracellular anticancer drugs, including DOX, vincristine, and paclitaxel, which led to a boost to the cell killing of the anticancer drugs and lowering their survival of the tumor cells. The aptamer d3-mediated MDR-reversal for effective chemotherapy was further verified in an in vivo animal model, and combination of aptamer d3 with DOX significantly improved the suppression of tumor growth by treating a xenograft HepG2/DOX tumor in vivo. This work demonstrates the feasibility of a therapeutic DNA aptamer as a tumor MDR-reversal agent, and combination of the selected aptamer with chemotherapeutic drugs shows great potential for liver cancer treatments.


Assuntos
Antineoplásicos , Resistencia a Medicamentos Antineoplásicos , Animais , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Quimioterapia Combinada , Linhagem Celular Tumoral
20.
ACS Sens ; 9(4): 2075-2082, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38557006

RESUMO

Wearable sweat sensors have achieved rapid development since they hold great potential in personalized health monitoring. However, a typical difficulty in practical processes is the control of working conditions for biorecognition elements, e.g., pH level and ionic strength in sweat may decrease the affinity between analytes and recognition elements. Here, we developed a wearable sensing device for cortisol detection in sweat using an aptamer as the recognition element. The device integrated functions of sweat collection, reagent prestorage, and signal conversion. Especially, the components of prestored reagents were optimized according to the inherent characteristics of sweat samples and electrodes, which allowed us to keep optimal conditions for aptamers. The sweat samples were transferred from the inlet of the device to the reagent prestored chamber, and the dry preserved reagents were rehydrated with sweat and then arrived at the aptamer-modified electrodes. Sweat samples of volunteers were analyzed by the wearable sensing device, and the results showed a good correlation with those of the ELISA kit. We believe that this convenient and reliable wearable sensing device has significant potential in self-health monitoring.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Hidrocortisona , Suor , Dispositivos Eletrônicos Vestíveis , Suor/química , Hidrocortisona/análise , Humanos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Eletrodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Indicadores e Reagentes/química
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