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1.
Acta Pharmacol Sin ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982150

RESUMO

Olfactory dysfunction is increasingly recognized as an early indicator of Alzheimer's disease (AD). Aberrations in GABAergic function and the excitatory/inhibitory (E/I) balance within the olfactory bulb (OB) have been implicated in olfactory impairment during the initial stages of AD. While the neuregulin 1 (NRG1)/ErbB4 signaling pathway is known to regulate GABAergic transmission in the brain and is associated with various neuropsychiatric disorders, its specific role in early AD-related olfactory impairment remains incompletely understood. This study demonstrated that olfactory dysfunction preceded cognitive decline in young adult APP/PS1 mice and was characterized by reduced levels of NRG1 and ErbB4 in the OB. Further investigation revealed that deletion of ErbB4 in parvalbumin interneurons reduced GABAergic transmission and increased hyperexcitability in mitral and tufted cells (M/Ts) in the OB, thereby accelerating olfactory dysfunction in young adult APP/PS1 mice. Additionally, ErbB4 deficiency was associated with increased accumulation of Aß and BACE1-mediated cleavage of APP, along with enhanced CDK5 signaling in the OB. NRG1 infusion into the OB was found to enhance GABAergic transmission in M/Ts and alleviate olfactory dysfunction in young adult APP/PS1 mice. These findings underscore the critical role of NRG1/ErbB4 signaling in regulating GABAergic transmission and E/I balance within the OB, contributing to olfactory impairment in young adult APP/PS1 mice, and provide novel insights for early intervention strategies in AD. This work has shown that ErbB4 deficiency increased the burden of Aß, impaired GABAergic transmission, and disrupted the E/I balance of mitral and tufted cells (M/Ts) in the OB, ultimately resulting in olfactory dysfunction in young adult APP/PS1 mice. NRG1 could enhance GABAergic transmission, rescue E/I imbalance in M/Ts, and alleviate olfactory dysfunction in young adult APP/PS1 mice. OB: olfactory bulb, E/I: excitation/inhibition, Pr: probability of release, PV: parvalbumin interneurons, Aß: ß-amyloid, GABA: gamma-aminobutyric acid.

2.
Chin J Cancer Res ; 36(3): 240-256, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38988488

RESUMO

Bruton's tyrosine kinase inhibitors (BTKis) have revolutionized the treatment of B-cell lymphomas. However, safety issues related to the use of BTKis may hinder treatment continuity and further affect clinical efficacy. A comprehensive and systematic expert consensus from a pharmacological perspective is lacking for safety issues associated with BTKi treatment. A multidisciplinary consensus working group was established, comprising 35 members from the fields of hematology, cardiovascular disease, cardio-oncology, clinical pharmacy, and evidence-based medicine. This evidence-based expert consensus was formulated using an evidence-based approach and the Delphi method. The Joanna Briggs Institute Critical Appraisal (JBI) tool and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach were used to rate the quality of evidence and grade the strength of recommendations, respectively. This consensus provides practical recommendations for BTKis medication based on nine aspects within three domains, including the management of common adverse drug events such as bleeding, cardiovascular events, and hematological toxicity, as well as the management of drug-drug interactions and guidance for special populations. This multidisciplinary expert consensus could contribute to promoting a multi-dimensional, comprehensive and standardized management of BTKis.

3.
Int Immunopharmacol ; 138: 112623, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38991630

RESUMO

OBJECTIVE: Bladder cancer (BCa) is a highly lethal urological malignancy characterized by its notable histological heterogeneity. Autophagy has swiftly emerged as a diagnostic and prognostic biomarker in diverse cancer types. Nonetheless, the currently accessible autophagy-related signature specific to BCa remains limited. METHODS: A refined autophagy-related signature was developed through a 10-fold cross-validation framework, incorporating 101 combinations of machine learning algorithms. The performance of this signature in predicting prognosis and response to immunotherapy was thoroughly evaluated, along with an exploration of potential drug targets and compounds. In vitro and in vivo experiments were conducted to verify the regulatory mechanism of hub gene. RESULTS: The autophagy-related prognostic signature (ARPS) has exhibited superior performance in predicting the prognosis of BCa compared to the majority of clinical features and other developed markers. Higher ARPS is associated with poorer prognosis and reduced sensitivity to immunotherapy. Four potential targets and five therapeutic agents were screened for patients in the high-ARPS group. In vitro and vivo experiments have confirmed that FKBP9 promotes the proliferation, invasion, and metastasis of BCa. CONCLUSIONS: Overall, our study developed a valuable tool to optimize risk stratification and decision-making for BCa patients.

4.
Med ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38986608

RESUMO

BACKGROUND: Gastric cancer is the fifth most common cancer and the fourth most common cause of cancer death worldwide, yet the prognosis of advanced disease remains poor. METHODS: This was a randomized, double-blinded, phase 2 trial (ClinicalTrials.gov: NCT04908813). Patients with locally advanced/metastatic HER2-positive gastric/gastroesophageal junction cancer and no prior systemic antitumor therapy were randomized 1:1:1 to 25 mg/kg HLX22 (a novel anti-HER2 antibody) + HLX02 (trastuzumab biosimilar) + oxaliplatin and capecitabine (XELOX) (group A), 15 mg/kg HLX22 + HLX02 + XELOX (group B), or placebo + HLX02 + XELOX (group C) in 3-week cycles. Primary endpoints were progression-free survival (PFS) and objective response rate (ORR) assessed by independent radiological review committee (IRRC). FINDINGS: Between November 29, 2021, and June 6, 2022, 82 patients were screened; 53 were randomized to group A (n = 18), B (n = 17), and C (n = 18). With 14.3 months of median follow-up, IRRC-assessed median PFS was prolonged with the addition of HLX22 (A vs. C, 15.1 vs. 8.2 months, hazard ratio [HR] 0.5 [95% confidence interval (CI) 0.17-1.27]; B vs. C, not reached vs. 8.2 months, HR 0.1 [95% CI 0.04-0.52]). Confirmed ORR was comparable among groups (A vs. B vs. C, 77.8% vs. 82.4% vs. 88.9%). Treatment-related adverse events (TRAEs) were observed in 18 (100%), 16 (94.1%), and 17 (94.4%) patients, respectively. One (5.6%) patient in group C reported a grade 5 TRAE. CONCLUSIONS: Adding HLX22 to HLX02 and XELOX prolonged PFS and enhanced antitumor response in the first-line treatment of HER2-positive gastric cancer, with manageable safety. FUNDING: Shanghai Henlius Biotech, Inc.

5.
Inorg Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014892

RESUMO

Ring contraction of metallacyclobutadiene to metallacyclopropene is rare because of the increasing strain from a four-membered ring to a three-membered one. Here we demonstrate a new series of reactions of metallabenzocyclobutadiene to metallabenzocyclopropene via density functional theory calculations. The results suggest that these reactions are thermodynamically favorable ranging from -17.4 to -29.4 kcal mol-1, and a low reaction barrier (10.3 kcal mol-1) is achieved when the metal center is Ru and the ligands are one cyanide and one chloride. Further analysis suggests that a strengthened binding energy helps stabilize the transition state in the protonation process. The aromaticity during the reaction was investigated using the electron density of delocalized bonds (EDDB), isomerization stabilization energy, and isodesmic reactions. The EDDB shows that the π-conjugation is disrupted in the intermediate, and then σ-aromaticity is generated and dominant in the products. Our findings could be helpful for experimentalists in developing novel ring contraction reactions driven by aromaticity.

6.
Inorg Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014904

RESUMO

Aromaticity is a fundamental concept in organic chemistry. Hyperconjugative aromaticity, also known as hyperconjugation-induced aromaticity, has evolved from its origin from main group substituents to transition metal analogues, establishing itself as an important category of aromaticity. Additionally, aromatic compounds comprising two sp3-carbon atoms have recently been reported both experimentally and computationally. However, what is the maximum number of sp3-hybridized atoms needed to maintain hyperconjugative aromaticity? Here, we report that hyperconjugative aromaticity can be achieved in hexa-substituted indoliums and octa-substituted pyrroliums, possessing three-five sp3-hybridized carbon/nitrogen atoms by means of density functional theory (DFT) calculations. The aromaticity was confirmed by using various aromaticity indices, i.e., NICS, MCI, and EDDB. Notably, the strong electron-donating ability and aurophilicity of Au(I) substituents play a pivotal role in maintaining the aromaticity and structural integrity. In addition, increasing the number of hyperconjugative centers will decrease the aromaticity in these five-membered rings. Our findings highlight the significance of transition metal substituents in hyperconjugative aromaticity and offer a novel approach for designing aromatic organometallics.

7.
Lancet Reg Health West Pac ; 48: 101121, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39040040

RESUMO

Background: Whether hepatitis B virus (HBV) infection of women prior to pregnancy can influence risk of congenital malformations in offspring remains controversial. We assessed the association between them by considering congenital malformations in the aggregate as well as risk of organs systems using a large national sample of Chinese women. Methods: We performed a record-linkage cohort study of women who participated in National Free Preconception Health Examination Project, between January 1, 2010, and December 31, 2019 for whom data on congenital malformations in their offspring were available from the National Population-Based Birth Defects Surveillance Network. A total of 498,968 linked records were obtained, of which 127,371 were excluded because HBV status before pregnancy was unknown, the records involved multiple pregnancies, or pre-pregnancy examinations were conducted after conception. Based on pre-pregnancy status, mothers were assigned to two categories of HBsAg- or HBsAg+ and, in certain analyses, to three categories of HBsAg-, HBsAg+/HBeAg- or HBsAg+/HBeAg+. Potential associations of serological status with risk of congenital malformations, considered separately or in aggregate, were explored using multilevel logistic regression. Factors that might influence such associations were also explored. Findings: Among the 371,597 women analyzed, 21,482 (5.78%) were HBsAg+ before pregnancy, and 8333 (2.24%) had a fetus or child diagnosed with congenital malformations, composed of 7744 HBsAg- women and 589 HBsAg+ women. HBsAg+ status was associated with increased risk of congenital malformations in the aggregate (OR 1.14, 95% CI 1.03-1.25) and of cardiovascular malformations specifically (OR 1.18, 95% CI 1.03-1.35). HBsAg+/HBeAg- status was associated with significantly higher risk of cardiovascular malformations (OR 1.19, 95% CI 1.01-1.39) as well as reproductive malformations (OR 1.51, 95% CI 1.02-2.23). Associations between HBsAg+ status before pregnancy and risk of congenital malformations was modified by alanine aminotransferase activity (P interaction < 0.05). Interpretation: Prepregnancy HBV infection might be associated with fetal malformations. This association needs further investigation to confirm whether it is a causal association, and assess whether antiviral therapy of women with HBsAg+ planning to conceive might reduce the risk of fetal malformations. Funding: The National Health Commission of the People's Republic of China, China; Science and Technology Department of Sichuan Province, China; and the Ministry of Science and Technology of the People's Republic of China.

8.
Anim Nutr ; 18: 57-71, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39035982

RESUMO

Dietary nutrient manipulation (e.g. protein fractions) could lower the environmental footprints of ruminants, especially reactive nitrogen (N). This study investigated the impacts of dietary soluble protein (SP) levels with decreased crude protein (CP) on intestinal N absorption, hindgut N metabolism, fecal microbiota and metabolites, and their linkage with N metabolism phenotype. Thirty-two male Hu sheep, with an age of six months and an initial BW of 40.37 ± 1.18 kg, were randomly assigned to four dietary groups. The control diet (CON), aligning with NRC standards, maintained a CP content of 16.7% on a dry matter basis. Conversely, the experimental diets (LPA, LPB, and LPC) featured a 10% reduction in CP compared with CON, accompanied by SP adjustments to 21.2%, 25.9%, and 29.4% of CP, respectively. Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine, ammonia, urea N, and fecal total short-chain fatty acids (SCFA) (P < 0.05). Notably, LPB and LPC exhibited increased total SCFA and propionate concentrations compared with LPA (P < 0.05). The enrichment of the Prevotella genus in fecal microbiota associated with energy metabolism and amino acid (AA) biosynthesis pathways was evident with SP levels in low-protein diets of approximately 25% to 30%. Moreover, LPB and LPC diets demonstrated a decrease in fecal NH 4 + -N and NO 2 - -N contents as well as urease activity, compared with CON (P < 0.05). Concomitantly, reductions in fecal glutamic acid dehydrogenase gene (gdh), nitrite reductase gene (nirS), and nitric oxide reductase gene (norB) abundances were observed (P < 0.05), pointing towards a potential reduction in reactive N production at the source. Of significance, the up-regulation of mRNA abundance of AA and peptide transporters in the small intestine (duodenum, jejunum, and ileum) and the elevated concentration of plasma AA (e.g. arginine, methionine, aspartate, glutamate, etc.) underscored the enhancement of N absorption and N efficiency. In summary, a 10% reduction in CP, coupled with an SP level of approximately 25% to 30%, demonstrated the potential to curtail reactive N emissions through fecal Prevotella enrichment and improve intestinal energy and N utilization efficiency.

9.
Materials (Basel) ; 17(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998162

RESUMO

This paper examines the accuracy and effectiveness of various beam theories in predicting the critical buckling loads and fundamental frequencies of functionally graded porous (FGP) beams whose material properties change continuously across the thickness. The beam theories considered are classical beam theory (CBT), first-order shear deformation beam theory (FSDBT), third-order shear deformation beam theory (TSDBT), and the broken-line hypothesis-based shear deformation beam theory (BSDBT). Governing equations for those beam theories are formulated by using the Hamilton's principle and are then solved by means of the generalised differential quadrature method. Finite element simulation solutions are provided as reference results to assess the predictions of those beam theories. Comprehensive numerical results are presented to evaluate the influences of the porosity distribution and coefficient, slenderness ratio, and boundary condition on the difference between theoretical predictions and simulation results. It is found that the differences significantly increase as the porosity coefficient rises, and this effect becomes more noticeable for the rigid beam with a smaller slenderness ratio. Nonetheless, the results produced by the BSDBT are always the closest to simulation ones. The findings in this paper will contribute to the establishment of more refined theories for the mechanical analysis of FGP structures.

10.
Foods ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998501

RESUMO

Lycium ruthenicum Murr. is rich in polysaccharides, and the polysaccharides in Lycium ruthenicum Murr. (LRPS) have various bioactivities, such as antioxidant activity, anti-tumor activity, neuroprotective activity, and immunomodulatory activity. It has broad prospects in the development of functional foods and pharmaceuticals. Researchers have found that the structural characteristics of LRPS, such as molecular weight, monosaccharide composition, primary structure, etc., have a significant impact on their bioactivities. Therefore, studying the structure of LRPS is of great significance in revealing their bioactivities and mechanisms. This study, based on introducing the preparation methods of LRPS, focuses on reviewing the research progress on the main structural characteristics, various bioactivities, and mechanisms of action of LRPS. In addition, the study provides prospects for the development of LRPS in the fields of food and medicine, aiming to provide theoretical support for its deep processing and application.

12.
Mol Cancer ; 23(1): 139, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970106

RESUMO

BACKGROUND: Radioresistance is the leading cause of death in advanced cervical cancer (CC). Dysregulation of RNA modification has recently emerged as a regulatory mechanism in radiation and drug resistance. We aimed to explore the biological function and clinical significance of 5-methylcytosine (m5C) in cervical cancer radiosensitivity. METHODS: The abundance of RNA modification in radiotherapy-resistant and sensitive CC specimens was quantified by liquid chromatography-tandem mass spectrometry. The essential RNA modification-related genes involved in CC radiosensitivity were screened via RNA sequencing. The effect of NSUN6 on radiosensitivity was verified in CC cell lines, cell-derived xenograft (CDX), and 3D bioprinted patient-derived organoid (PDO). The mechanisms of NSUN6 in regulating CC radiosensitivity were investigated by integrative m5C sequencing, mRNA sequencing, and RNA immunoprecipitation. RESULTS: We found a higher abundance of m5C modification in resistant CC samples, and NSUN6 was the essential m5C-regulating gene concerning radiosensitivity. NSUN6 overexpression was clinically correlated with radioresistance and poor prognosis in cervical cancer. Functionally, higher NSUN6 expression was associated with radioresistance in the 3D PDO model of cervical cancer. Moreover, silencing NSUN6 increased CC radiosensitivity in vivo and in vitro. Mechanistically, NDRG1 was one of the downstream target genes of NSUN6 identified by integrated m5C-seq, mRNA-seq, and functional validation. NSUN6 promoted the m5C modification of NDRG1 mRNA, and the m5C reader ALYREF bound explicitly to the m5C-labeled NDRG1 mRNA and enhanced NDRG1 mRNA stability. NDRG1 overexpression promoted homologous recombination-mediated DNA repair, which in turn led to radioresistance in cervical cancer. CONCLUSIONS: Aberrant m5C hypermethylation and NSUN6 overexpression drive resistance to radiotherapy in cervical cancer. Elevated NSUN6 expression promotes radioresistance in cervical cancer by activating the NSUN6/ALYREF-m5C-NDRG1 pathway. The low expression of NSUN6 in cervical cancer indicates sensitivity to radiotherapy and a better prognosis.


Assuntos
5-Metilcitosina , Proteínas de Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , RNA Mensageiro , Tolerância a Radiação , Neoplasias do Colo do Útero , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia , Humanos , Feminino , Tolerância a Radiação/genética , 5-Metilcitosina/metabolismo , 5-Metilcitosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Animais , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linhagem Celular Tumoral , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto , Metiltransferases/genética , Metiltransferases/metabolismo
13.
Cell Death Dis ; 15(7): 485, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971772

RESUMO

The discovery of novel oncotargets for glioma is of immense significance. We here explored the expression patterns, biological functions, and underlying mechanisms associated with ORC6 (origin recognition complex 6) in glioma. Through the bioinformatics analyses, we found a significant increase in ORC6 expression within human glioma tissues, correlating with poorer overall survival, higher tumor grade, and wild-type isocitrate dehydrogenase status. Additionally, ORC6 overexpression is detected in glioma tissues obtained from locally-treated patients and across various primary/established glioma cells. Further bioinformatics scrutiny revealed that genes co-expressed with ORC6 are enriched in multiple signaling cascades linked to cancer. In primary and immortalized (A172) glioma cells, depleting ORC6 using specific shRNA or Cas9-sgRNA knockout (KO) significantly decreased cell viability and proliferation, disrupted cell cycle progression and mobility, and triggered apoptosis. Conversely, enhancing ORC6 expression via a lentiviral construct augmented malignant behaviors in human glioma cells. ORC6 emerged as a crucial regulator for the expression of key oncogenic genes, including Cyclin A2, Cyclin B2, and DNA topoisomerase II (TOP2A), within glioma cells. Silencing or KO of ORC6 reduced the mRNA and protein levels of these genes, while overexpression of ORC6 increased their expression in primary glioma cells. Bioinformatics analyses further identified RBPJ as a potential transcription factor of ORC6. RBPJ shRNA decreased ORC6 expression in primary glioma cells, while its overexpression increased it. Additionally, significantly enhanced binding between the RBPJ protein and the proposed ORC6 promoter region was detected in glioma tissues and cells. In vivo experiments demonstrated a significant reduction in the growth of patient-derived glioma xenografts in the mouse brain subsequent to ORC6 KO. ORC6 depletion, inhibited proliferation, decreased expression of Cyclin A2/B2/TOP2A, and increased apoptosis were detected within these ORC6 KO intracranial glioma xenografts. Altogether, RBPJ-driven ORC6 overexpression promotes glioma cell growth, underscoring its significance as a promising therapeutic target.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma , Complexo de Reconhecimento de Origem , Animais , Humanos , Masculino , Camundongos , Apoptose/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Ciclina A2/metabolismo , Ciclina A2/genética , Ciclina B2/metabolismo , Ciclina B2/genética , DNA Topoisomerases Tipo II/metabolismo , DNA Topoisomerases Tipo II/genética , Glioma/genética , Glioma/patologia , Glioma/metabolismo , Camundongos Nus , Complexo de Reconhecimento de Origem/metabolismo , Complexo de Reconhecimento de Origem/genética
14.
Int J Mol Sci ; 25(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39000408

RESUMO

Nucleotide-binding and leucine-rich repeat receptors (NLRs) are the most important and largest class of immune receptors in plants. The Pi36 gene encodes a canonical CC-NBS-LRR protein that confers resistance to rice blast fungal infections. Here, we show that the CC domain of Pi36 plays a role in cell death induction. Furthermore, self-association is required for the CC domain-mediated cell death, and the self-association ability is correlated with the cell death level. In addition, the NB-ARC domain may suppress the activity of the CC domain through intramolecular interaction. The mutations D440G next to the RNBS-D motif and D503V in the MHD motif autoactivated Pi36, but the mutation K212 in the P-loop motif inhibited this autoactivation, indicating that nucleotide binding of the NB-ARC domain is essential for Pi36 activation. We also found that the LRR domain is required for D503V- and D440G-mediated Pi36 autoactivation. Interestingly, several mutations in the CC domain compromised the CC domain-mediated cell death without affecting the D440G- or D503V-mediated Pi36 autoactivation. The autoactivate Pi36 variants exhibited stronger self-associations than the inactive variants. Taken together, we speculated that the CC domain of Pi36 executes cell death activities, whereas the NB-ARC domain suppressed CC-mediated cell death via intermolecular interaction. The NB-ARC domain releases its suppression of the CC domain and strengthens the self-association of Pi36 to support the CC domain, possibly through nucleotide exchange.


Assuntos
Proteínas NLR , Oryza , Proteínas de Plantas , Oryza/metabolismo , Oryza/genética , Oryza/imunologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas NLR/metabolismo , Proteínas NLR/genética , Proteínas NLR/química , Morte Celular , Mutação , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Domínios Proteicos , Resistência à Doença/genética , Imunidade Vegetal/genética
15.
Org Lett ; 26(28): 5984-5988, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38975861

RESUMO

Presented herein is the exploration of a novel non-covalent anion-carbonyl (X-···C═O) interaction using aromatic imides as receptors and halides as lone pair donors. Combined theoretical calculations and experimental methods including 13C NMR, IR, and crystallographic analyses were performed to provide the physical origin and experimental evidence of anion-carbonyl interactions. The EDA analysis (energy decomposition analysis) based on DFT calculation indicates that electrostatic terms are the dominant contributions for the binding energy while electron delocalization also significantly contributes alongside the electrostatic attraction. Orbital interaction (n → π*) involving the delocalization of halide lone pairs on the carbonyl antibonding orbitals was visualized with NBO (Natural Bond Orbital) analysis. 13C NMR and IR spectra demonstrated upfield chemical shifts and red-shift frequency of hosts upon the addition of halides, reflecting the effect of orbital overlap between the halide lone pairs and π* of carbonyl (n → π* contribution). The anion-carbonyl interactions were directly revealed by X-ray structural analysis of anion and benzene triimide complexes.

16.
Nanotechnology ; 35(40)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38991512

RESUMO

CsPbBr3quantum dots (QDs) have excellent optical properties and good phase stability, but the long-chain ligands on their surfaces affect the charge transfer between QDs. Here, we propose a simple ligand exchange strategy: solution-phase ligand exchange. By adding an acetone solution of phenylethylammonium bromide to the purification process of CsPbBr3QDs, the long-chain ligands were effectively replaced and the electric coupling between QDs was improved. As a result, the power conversion efficiency of the solar cell was increased from 1.95% to 2.83%. Meanwhile, the stability of the devices was significantly improved in the unencapsulated case.

17.
Int J Med Sci ; 21(9): 1710-1717, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006839

RESUMO

The Aim of this study was to investigate the long-term impact of left atrial appendage occlusion (LAAO) on cardiac function and structure in patients with non-valvular atrial fibrillation (NVAF). 157 patients with NVAF who underwent LAAO or combined with ablation were included and divided into simple LAAO group or combined group. Long term impact of LAAO on cardiac function and structure were evaluated. Results showed that the procedures were performed successfully with 6.4% complications. During follow-up, there was a significant decrease of left atrial anteroposterior diameter (LAAD) at 6 months and a significant increase of left ventricular end-diastolic dimension (LVEDD) at 12 months after LAAO. A significant decrease in plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) was noted at 3 months, 6 months and 12 months after procedure. There was a significant decrease of LAAD, LVEDD, left ventricular end-systolic dimension (LVESD) and NT-proBNP levels in combined group at 3 months, 6 months and 12 months post- procedure, while an increase of left ventricular ejection fraction (LVEF). Meanwhile, no significant change of LAAD, LVEDD, LVESD, NT-proBNP and LVEF was seen in simple LAAO group at 3 months follow-up, but a decrease of NT-proBNP during 6 months and 12 months follow-up. Compared with simple LAAO group, combined group was associated with a significant increase of residual flow. In conclusion, LAAO has no significant effect on cardiac structure and function but can significantly reduce NT-proBNP. The improvement of cardiac structure and function in combined therapy comes from the result of ablation, not LAAO.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Peptídeo Natriurético Encefálico , Humanos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/sangue , Apêndice Atrial/cirurgia , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Peptídeo Natriurético Encefálico/sangue , Ablação por Cateter/métodos , Resultado do Tratamento , Fragmentos de Peptídeos/sangue , Função Ventricular Esquerda/fisiologia , Volume Sistólico , Seguimentos
18.
Anal Chem ; 96(29): 11853-11861, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38989993

RESUMO

Cardiac myosin-binding protein C (cMyBP-C) is a novel cardiac marker of acute myocardial infarction (AMI) and acute cardiac injuries (ACI). Construction of point-of-care testing techniques capable of sensing cMyBP-C with high sensitivity and precision is urgently needed. Herein, we synthesized an Au@NGQDs@Au/Ag multi-shell nanoUrchins (MSNUs), and then applied it in a colorimetric/SERS dual-mode immunoassay for detection of cMyBP-C. The MSNUs displayed superior stability, colorimetric brightness, and SERS enhancement ability with an enhanced factor of 5.4 × 109, which were beneficial to improve the detection capability of test strips. The developed MSNU-based test strips can achieve an ultrasensitive immunochromatographic assay of cMyBP-C in both colorimetric and SERS modes with the limits of detection as low as 19.3 and 0.77 pg/mL, respectively. Strikingly, this strip was successfully applied to analyze actual plasma samples with significantly better sensitivity, negative predictive value, and accuracy than commercially available gold test strips. Notably, this method possessed a wide range of application scenarios via combining with a color recognizer application named Color Grab on the smartphone, which can meet various needs of different users. Overall, our MSNU-based test strip as a mobile health monitoring tool shows excellent sensitivity, reproducibility, and rapid detection of the cMyBP-C, which holds great potential for the early clinic diagnosis of AMI and ACI.


Assuntos
Proteínas de Transporte , Ouro , Humanos , Imunoensaio/métodos , Proteínas de Transporte/sangue , Ouro/química , Limite de Detecção , Colorimetria/métodos , Nanopartículas Metálicas/química , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/sangue , Análise Espectral Raman/métodos
19.
Nat Commun ; 15(1): 6120, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033152

RESUMO

Extremely large magnetoresistance (XMR) is highly applicable in spintronic devices such as magnetic sensors, magnetic memory, and hard drives. Typically, XMR is found in Weyl semimetals characterized by perfect electron-hole symmetry or exceptionally high electric conductivity and mobility. Our study explores this phenomenon in a recently developed graphene moiré system, which demonstrates XMR owing to its topological structure and high-quality crystal formation. We investigate the electronic properties of three-dimensional intertwined twisted graphene spirals (TGS), manipulating the screw dislocation axis to achieve a rotation angle of 7.3°. Notably, at 14 T and 2 K, the magnetoresistance of these structures reaches 1.7 × 107%, accompanied by a metal-insulator transition as the temperature increases. This transition becomes noticeable when the magnetic field exceeds a minimal threshold of approximately 0.1 T. These observations suggest the possible existence of complex, correlated states within the partially filled three-dimensional Landau levels of the 3D TGS system. Our findings open up possibilities for achieving XMR by engineering the topological structure of 2D layered moiré systems.

20.
Science ; : eadj3742, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39024378

RESUMO

Edge states of a topological insulator can be used to explore fundamental science emerging at the interface of low dimensionality and topology. Achieving a robust conductance quantization, however, has proven challenging for helical edge states. Here we show wide resistance plateaus in kink states - a manifestation of the quantum valley Hall effect in Bernal bilayer graphene - quantized to the predicted value at zero magnetic field. The plateau resistance has a very weak temperature dependence up to 50 Kelvin and is flat within a dc bias window of tens of mV. We demonstrate the electrical operation of a topology-controlled switch with an on/off ratio of 200. These results demonstrate the robustness and tunability of the kink states and its promise in constructing electron quantum optics devices.

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