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An asymmetric intramolecular spiro-amination to high steric hindering α-C-H bond of 1,3-dicarbonyl via nitrene transfer using inactive aryl azides has been carried out by developing a novel Cp*Ir(III)-SPDO (spiro-pyrrolidine oxazoline) catalyst, thereby enabling the first successful construction of structurally rigid spiro-quaternary indolinone cores with moderate to high yields and excellent enantioselectivities. DFT computations support the presence of double bridging H-F bonds between [SbF6]- and both the ligand and substrate, which favors the plane-differentiation of the enol π-bond for nitrenoid attacking. These findings open up numerous opportunities for the development of new asymmetric nitrene transfer systems.
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BACKGROUND: Chronic total occlusions (CTO) occur in about 20% of patients referred for coronary angiography, and right coronary artery (RCA) CTO has been reported in 38-50% of the entire CTO population. Limited data on angiographic and procedural characteristics of RCA-CTO and the risk of adverse cardiac events asks for a detailed study. METHODS: From 2010 to 2013, patients with attempted revascularization of at least one CTO lesion were included and followed up to 5 years after PCI. Eligible patients are assigned to RCA-CTO and non-RCA-CTO groups based on their target vessels. The primary endpoint was major adverse cardiovascular events (MACEs; a composite of all-cause death, myocardial infarction (MI) or rehospitalization for heart failure), and secondary endpoints were cardiac death, target lesion revascularization (TLR) and target vessel revascularization (TVR). RESULTS: The present study included 2659 eligible patients, among which 1285 patients were assigned to the RCA-CTO group, whereas 1374 patients were assigned to the non-RCA-CTO group. Lesions in RCA had longer lesion length, higher J-CTO score, higher rates of severe vessel tortuosity, a higher percentage of Rentrop grade 2-3, and more likely to be re-try lesion than those in LAD or LCX (all P < 0.01). CTO lesions in RCA reached less successful recanalization and post-procedural TIMI 3 flow (all <0.01). Multivariate Cox analysis revealed that RCA-CTO was not associated with primary outcome MACEs. Besides MACEs, RCA-CTO was also not associated with cardiac death, but was significantly associated with TLR and TVR (adjusted HR: 1.37 [95% CI:1.07-1.76], P = 0.01; adjusted HR: 1.43 [95% CI:1.13-1.82], P = 0.003). CONCLUSION: RCA-CTO lesions, which had more complex angiographic features, independently contributed to TLR and TVR but not to MACEs or cardiac death in the 5 years of follow-up.
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A protocol for the electrooxidative [3+2] annulation to generate indolo[2,3-b]indoles in an undivided cell is reported. It exhibits good yields with excellent regioselectivities and tolerates various functional groups without external chemical oxidants. Cyclic voltammetry and density functional theory calculations indicate that the [3+2] annulation is initiated by the simultaneous anodic oxidation of indole and aniline derivatives, and the step to determine the rate relies on the combination of radical cations.
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An intensive phytochemical investigation into the fruits of Schisandra chinensis afforded 28 triterpenoids incorporating diverse backbones with methyl-migration, ring-expansion and ring-opening features. Among them, ten compounds (1-10) including three likely extracting artefacts (8-10) were described for the first time. Their structures were fully characterized by comprehensive spectroscopic analyses, with the absolute configurations established via electronic circular dichroism and Mosher's NMR techniques. Preliminary biological evaluations revealed that nine isolates showed inhibitory activity against the hyperglycemic target α-glycosidase and 12 compounds exerted cytotoxicity toward three female tumor cell lines (Hela (cervical), MDA-MB231 and MCF-7 (breast)). Compound 6 exhibited the most promising potency on all the three tested cancer cells, and further assessment demonstrated that it could induce significant cell apoptosis and cycle arrest, as well as suppress cell migration, by regulating relevant proteins in MDA-MB231 cells.
Assuntos
Antineoplásicos Fitogênicos , Apoptose , Frutas , Inibidores de Glicosídeo Hidrolases , Compostos Fitoquímicos , Schisandra , Triterpenos , Schisandra/química , Humanos , Frutas/química , Estrutura Molecular , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Apoptose/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , ChinaRESUMO
A novel ion exchange strategy has been developed to enable the asymmetric construction of axially chiral sulfone-containing styrenes. This approach provides a practical synthesis pathway for various axially chiral sulfone-containing styrenes with good yields, exceptional enantioselectivities, and nearly complete E/Z selectivities. Additionally, the reaction mechanism is elucidated in detail through density functional theory (DFT) calculations.
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Tracheal stenosis is a rare but life-threatening disease in preterm infants. Misdiagnosis as congenital tracheal stenosis is common, making surgical management challenging. This report presents a case of a preterm infant with tracheal stenosis and congenital heart malformation treated with ECMO-assisted tracheal resection and end-to-end anastomosis. A male infant was born at 30 weeks of gestation with severe asphyxia, cardiac insufficiency, and pneumonia. Following failed medical treatment, fiberoptic bronchoscopy confirmed mid-tracheal to carinal stenosis. After a 2-week treatment course, ECMO-assisted tracheal resection and end-to-end anastomosis were performed successfully. This case confirms the feasibility of tracheal resection and end-to-end anastomosis in low-weight, preterm infants with tracheal stenosis born at 30 weeks gestation. The utilization of ECMO for oxygenation during surgery provides a clear surgical field and shorter operating time. Surgical intervention may be necessary for neonatal tracheal stenosis depending on the clinical presentation.
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Lung adenocarcinoma (LUAD) is characterized by a high incidence rate and mortality. Recently, POC1 centriolar protein A (POC1A) has emerged as a potential biomarker for various cancers, contributing to cancer onset and development. However, the association between POC1A and LUAD remains unexplored. We extracted The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) data sets to analyse the differential expression of POC1A and its relationship with clinical stage. Additionally, we performed diagnostic receiver operator characteristic (ROC) curve analysis and Kaplan-Meier (KM) survival analysis to assess the diagnostic and prognostic value of POC1A in LUAD. Furthermore, we investigated the correlation between POC1A expression and immune infiltration, tumour mutation burden (TMB), immune checkpoint expression and drug sensitivity. Finally, we verified POC1A expression using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). Cell experiments were conducted to validate the effect of POC1A expression on the proliferation, migration and invasion of lung cancer cells. POC1A exhibited overexpression in most tumour tissues, and its overexpression in LUAD was significantly correlated with late-stage presentation and poor prognosis. The high POC1A expression group showed lower levels of immune infiltration but higher levels of immune checkpoint expression and TMB. Moreover, the high POC1A expression group demonstrated sensitivity to multiple drugs. In vitro experiments confirmed that POC1A knockdown led to decreased proliferation, migration, and invasion of lung cancer cells. Our findings suggest that POC1A may contribute to tumour development by modulating the cell cycle and immune cell infiltration. It also represents a potential therapeutic target and marker for the diagnosis and prognosis of LUAD.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Divisão Celular , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Neoplasias Pulmonares/genética , Regulação para Cima/genéticaRESUMO
Although more than 30 different types of neuropeptides have been identified in various cell types and circuits of the cerebellum, their unique functions in the cerebellum remain poorly understood. Given the nature of their diffuse distribution, peptidergic systems are generally assumed to exert a modulatory effect on the cerebellum via adaptively tuning neuronal excitability, synaptic transmission, and synaptic plasticity within cerebellar circuits. Moreover, cerebellar neuropeptides have also been revealed to be involved in the neurogenetic and developmental regulation of the developing cerebellum, including survival, migration, differentiation, and maturation of the Purkinje cells and granule cells in the cerebellar cortex. On the other hand, cerebellar neuropeptides hold a critical position in the pathophysiology and pathogenesis of many cerebellar-related motor and psychiatric disorders, such as cerebellar ataxias and autism. Over the past two decades, a growing body of evidence has indicated neuropeptides as potential therapeutic targets to ameliorate these diseases effectively. Therefore, this review focuses on eight cerebellar neuropeptides that have attracted more attention in recent years and have significant potential for clinical application associated with neurodegenerative and/or neuropsychiatric disorders, including brain-derived neurotrophic factor, corticotropin-releasing factor, angiotensin II, neuropeptide Y, orexin, thyrotropin-releasing hormone, oxytocin, and secretin, which may provide novel insights and a framework for our understanding of cerebellar-related disorders and have implications for novel treatments targeting neuropeptide systems.
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Doenças Cerebelares , Neuropeptídeos , Humanos , Cerebelo/metabolismo , Células de Purkinje/metabolismo , Neurônios/metabolismo , Córtex Cerebelar/metabolismo , Neuropeptídeos/metabolismo , Doenças Cerebelares/patologiaRESUMO
Aliphatic allylic amines are common in natural products and pharmaceuticals. The oxidative intermolecular amination of C(sp3)-H bonds represents one of the most straightforward strategies to construct these motifs. However, the utilization of widely internal alkenes with amines in this transformation remains a synthetic challenge due to the inefficient coordination of metals to internal alkenes and excessive coordination with aliphatic and aromatic amines, resulting in decreasing the reactivity of the catalyst. Here, we present a regioselective Cu-catalyzed oxidative allylic C(sp3)-H amination of internal olefins with azodiformates to these problems. A removable bidentate directing group is used to control the regiochemistry and stabilize the π-allyl-metal intermediate. Noteworthy is the dual role of azodiformates as both a nitrogen source and an electrophilic oxidant for the allylic C-H activation. This protocol features simple conditions, remarkable scope and functional group tolerance as evidenced by >40 examples and exhibits high regioselectivity and excellent E/Z selectivity.