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1.
J Org Chem ; 89(8): 5560-5572, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38564232

RESUMO

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

2.
Org Biomol Chem ; 22(12): 2409-2413, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38411219

RESUMO

A convenient, efficient and practical approach for the synthesis of S-quinolyl phosphorothioates via cheap TsCl promoted deoxygenative C2-H phosphorothiolation of quinoline N-oxides with readily available triethylammonium O,O-dialkylphosphorothioates was developed. The reaction performed well under transition-metal-free conditions at room temperature with a very short reaction time (10-20 min). Preliminary studies showed that the current transformation underwent a nucleophilic substitution process.

3.
Org Biomol Chem ; 22(18): 3740-3745, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38651658

RESUMO

An efficient and practical method for the synthesis of 3-alkenylquinoxalinones containing the SCF3 group has been readily developed through a three-component radical cascade reaction involving quinoxalinones, alkynes and AgSCF3. The reaction was found to be compatible with a variety of substrates and exhibited a high functional group tolerance and complete E-selectivity. The preliminary study suggests the involvement of a SCF3 radical in the transformation.

4.
Molecules ; 29(12)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38930928

RESUMO

A mild, efficient and practical protocol for the preparation of 2-sulfonylquinolines through CS2/Et2NH-induced deoxygenative C2-H sulfonylation of quinoline N-oxides with readily available RSO2Cl was developed. The reaction proceeded well under transition-metal-free conditions and exhibited a wide substrate scope and functional group tolerance. The preliminary studies suggested that the nucleophilic sulfonyl sources were generated in situ via the reaction of CS2, Et2NH and sulfonyl chlorides.

5.
Molecules ; 29(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38474508

RESUMO

The incorporation of amide groups into biologically active molecules has been proven to be an efficient strategy for drug design and discovery. In this study, we present a simple and practical method for the synthesis of amide-containing quinazolin-4(3H)-ones under transition-metal-free conditions. This is achieved through a carbamoyl-radical-triggered cascade cyclization of N3-alkenyl-tethered quinazolinones. Notably, the carbamoyl radical is generated in situ from the oxidative decarboxylative process of oxamic acids in the presence of (NH4)2S2O8.

6.
Chemistry ; 29(46): e202301390, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37280159

RESUMO

Chemodivergent tandem radical cyclization offers exciting possibilities for the synthesis of structurally diverse cyclic compounds. Herein, we revealed a chemodivergent tandem cyclization of alkene-substituted quinazolinones under metal- and base-free conditions, this transformation is initiated by alkyl radicals produced from oxidant-induced α-C(sp3 )-H functionalization of alkyl nitriles or esters. The reaction resulted in the selective synthesis of a series of mono- and di-alkylated ring-fused quinazolinones by modulating the loading of oxidant, reaction temperature, and reaction time. Mechanistic investigations show that the mono-alkylated ring-fused quinazolinones is constructed by the key process of 1,2-hydrogen shift, whereas the di-alkylated ring-fused quinazolinones is mainly achieved through crucial steps of resonance and proton transfer. This protocol is the first example of remote second alkylation on the aromatic ring via α-C(sp3 )-H functionalization and difunctionalization achieved by association of two unsaturated bonds in radical cyclization.

7.
Genet Res (Camb) ; 2023: 5517445, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026448

RESUMO

Glioma is a highly aggressive form of brain cancer characterized by limited treatment options and poor patient prognosis. In this study, we aimed to elucidate the oncogenic role of thymosin beta-10 (TMSB10) in glioma through comprehensive analyses of patient data from the TCGA and GTEx databases. Our investigation encompassed several key aspects, including the analysis of patients' clinical characteristics, survival analysis, in vitro and in vivo functional experiments, and the exploration of correlations between TMSB10 expression and immune cell infiltration. Our findings revealed a significant upregulation of TMSB10 expression in glioma tissues compared to normal brain tissues, with higher expression levels observed in tumors of advanced histological grades. Moreover, we observed positive correlations between TMSB10 expression and patient age, while no significant association with gender was detected. Additionally, TMSB10 exhibited marked elevation in gliomas with wild-type IDH and noncodeletion of 1p/19q. Survival analysis indicated that high TMSB10 expression was significantly associated with worse overall survival, disease-specific survival, and progression-free survival in glioma patients. Functionally, knockdown of TMSB10 in glioma cells resulted in reduced cellular growth rates and impaired tumor growth in xenograft models. Furthermore, our study revealed intriguing correlations between TMSB10 expression and immune cell infiltration within the tumor microenvironment. Specifically, TMSB10 showed negative associations with plasmacytoid dendritic cells (pDC) and γδ T cells (Tgd), while displaying positive correlations with neutrophils and macrophages. These findings collectively provide valuable insights into the oncogenic properties of TMSB10 in glioma, suggesting its potential as a therapeutic target and a biomarker for patient stratification.


Assuntos
Neoplasias Encefálicas , Glioma , Timosina , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Relevância Clínica , Glioma/genética , Glioma/patologia , Prognóstico , Análise de Sobrevida , Timosina/genética , Timosina/metabolismo , Microambiente Tumoral
8.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38015052

RESUMO

A Gram-stain-positive, aerobic, rod-shaped, non-motile, yellowish and glossy strain, C31T, was isolated from a wetland plant Polygonum lapathifolium L. located south of Poyang Lake, Jiangxi Province, PR China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain C31T showed similarity values of lower than 97.0 % to other type species belonging to the genus Paenibacillus. The genomic average nucleotide identity values between strain C31T and its reference type species ranged from 68.9-70.9 % and the digital DNA-DNA hybridization values were lower than 27.8 %. The genomic DNA G+C content of strain C31T was 41.9 mol%. The optimal growth temperature, pH and NaCl concentration were 37 °C, pH 7 and 0.5 %, respectively. The major cellular fatty acids (>5.0 %) of strain C31T were anteiso-C15 : 0 (73.7 %), anteiso-C17 : 0 (8.4 %) and iso-C15 : 0 (5.2 %). The polar lipids of strain C31T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified phospholipids. The respiratory quinone was MK-7. Based on these phylogenetic and phenotypic characterizations, strain C31T represents a novel species within the genus Paenibacillus. Therefore, the proposed name for this newly identified species is Paenibacillus polygoni sp. nov. and the type strain is C31T (=CCTCC AB 2022349T=KCTC 43565T).


Assuntos
Paenibacillus , Polygonum , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Áreas Alagadas , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Paenibacillus/genética
9.
Org Biomol Chem ; 21(19): 4109-4113, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37128965

RESUMO

A photocatalytic three-component cascade reaction of quinoxalin-2(1H)-ones, alkenes, and sulfinic acids under metal-, strong oxidant-, and external photocatalyst-free conditions was developed. The reaction was performed at room temperature using air as a green oxidant. Various sulfonated quinoxalin-2(1H)-ones were obtained in satisfactory yields with good functional group compatibility. The preliminary study showed that the current transformation was enabled by the formation of an electron donor-acceptor (EDA) complex between quinoxalin-2(1H)-ones and sulfinic acids.

10.
Org Biomol Chem ; 21(45): 9086-9090, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37946513

RESUMO

An environmentally benign protocol that provides various S-quinolyl xanthates via a ball milling enabled cross coupling reaction of haloquinolines and readily available potassium O-alkyl xanthates is first reported. The reaction proceeded well under mild, transition metal- and solvent-free conditions, making it an attractive method for the introduction of xanthates into the quinoline scaffold.

11.
Nano Lett ; 22(10): 3969-3975, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35506587

RESUMO

Chromatic aberration is a major challenge faced by metalenses. Current methods to achieve broadband achromatic operation in metalenses usually suffer from limited size, numerical aperture, and working bandwidth due to the finite group delay of meta-atoms, thus restricting the range of practical applications. Multiwavelength achromatic metalenses can overcome those limitations, making it possible to realize larger numerical aperture (NA) and sizes simultaneously. However, they usually require three layers, which increases their fabrication complexity, and have only been demonstrated in small sizes, with low numerical aperture and modest efficiencies. Here, we demonstrate a 1 mm diameter red-green-blue achromatic metalens doublet with a designed NA of 0.8 and successfully apply the metalens in a digital imaging system. This work shows the potential of the doublet metasurfaces, extending their applications to digital imaging systems such as digital projectors, virtual reality glasses, high resolution microscopies, etc.


Assuntos
Processamento de Imagem Assistida por Computador , Lentes , Cor , Humanos , Processamento de Imagem Assistida por Computador/instrumentação
12.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835261

RESUMO

Protein kinase Cα (PKCα/PRKCA) is a crucial regulator of circadian rhythm and is associated with human mental illnesses such as autism spectrum disorders and schizophrenia. However, the roles of PRKCA in modulating animal social behavior and the underlying mechanisms remain to be explored. Here we report the generation and characterization of prkcaa-deficient zebrafish (Danio rerio). The results of behavioral tests indicate that a deficiency in Prkcaa led to anxiety-like behavior and impaired social preference in zebrafish. RNA-sequencing analyses revealed the significant effects of the prkcaa mutation on the expression of the morning-preferring circadian genes. The representatives are the immediate early genes, including egr2a, egr4, fosaa, fosab and npas4a. The downregulation of these genes at night was attenuated by Prkcaa dysfunction. Consistently, the mutants demonstrated reversed day-night locomotor rhythm, which are more active at night than in the morning. Our data show the roles of PRKCA in regulating animal social interactions and link the social behavior defects with a disturbed circadian rhythm.


Assuntos
Comportamento Animal , Ritmo Circadiano , Proteína Quinase C-alfa , Comportamento Social , Peixe-Zebra , Animais , Humanos , Ansiedade , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Fatores de Transcrição de Resposta de Crescimento Precoce , Transtornos do Sono do Ritmo Circadiano/genética , Peixe-Zebra/genética , Peixe-Zebra/fisiologia , Proteína Quinase C-alfa/genética , Proteína Quinase C-alfa/metabolismo
13.
Int J Mol Sci ; 24(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36902464

RESUMO

A convenient and practical method for the synthesis of bioactive ester-containing chroman-4-ones through the cascade radical cyclization of 2-(allyloxy)arylaldehydes and oxalates is described. The preliminary studies suggest that an alkoxycarbonyl radical might be involved in the current transformation, which was generated via the decarboxylation of oxalates in the presence of (NH4)2S2O8.


Assuntos
Ésteres , Oxalatos , Metais , Ciclização , Cromanos
14.
Small ; 18(47): e2203956, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36228096

RESUMO

Flexibility/wearable electronics such as strain/pressure sensors in human-machine interactions (HMI) are highly developed nowadays. However, challenges remain because of the lack of flexibility, fatigue resistance, and versatility, leading to mechanical damage to device materials during practical applications. In this work, a triple-network conductive hydrogel is fabricated by combining 2D Ti3 C2 Tx nanosheets with two kinds of 1D polymer chains, polyacrylamide, and polyvinyl alcohol. The Ti3 C2 Tx nanosheets act as the crosslinkers, which combine the two polymer chains of PAM and PVA via hydrogen bonds. Such a unique structure endows the hydrogel (MPP-hydrogel) with merits such as mechanical ultra-robust, super-elasticity, and excellent fatigue resistance. More importantly, the introduced Ti3 C2 Tx nanosheets not only enhance the hydrogel's conductivity but help form double electric layers (DELs) between the MXene nanosheets and the free water molecules inside the MPP-hydrogel. When the MPP-hydrogel is used as the electrode of the triboelectric nanogenerator (MPP-TENG), due to the dynamic balance of the DELs under the initial potential difference generated from the contact electrification as the driving force, an enhanced electrical output of the TENG is generated. Moreover, flexible strain/pressure sensors for tiny and low-frequency human motion detection are achieved. This work demonstrates a promising flexible electronic material for e-skin and HMI.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Humanos , Hidrogéis/química , Condutividade Elétrica , Polímeros , Eletrônica
15.
Mol Psychiatry ; 26(11): 6630-6642, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33963283

RESUMO

The non-Mendelian features of phenotypic variations within monozygotic twins are likely complicated by environmental modifiers of genetic effects that have yet to be elucidated. Here, we performed methylome and genome analyses of blood DNA from psychiatric disorder-discordant monozygotic twins to study how allele-specific methylation (ASM) mediates phenotypic variations. We identified that thousands of genetic variants with ASM imbalances exhibit phenotypic variation-associated switching at regulatory loci. These ASMs have plausible causal associations with psychiatric disorders through effects on interactions between transcription factors, DNA methylations, and other epigenomic markers and then contribute to dysregulated gene expression, which eventually increases disease susceptibility. Moreover, we also experimentally validated the model that the rs4854158 alternative C allele at an ASM switching regulatory locus of EIPR1 encoding endosome-associated recycling protein-interacting protein 1, is associated with demethylation and higher RNA expression and shows lower TF binding affinities in unaffected controls. An epigenetic ASM switching induces C allele hypermethylation and then recruits repressive Polycomb repressive complex 2 (PRC2), reinforces trimethylation of lysine 27 on histone 3 and inhibits its transcriptional activity, thus leading to downregulation of EIPR1 in schizophrenia. Moreover, disruption of rs4854158 induces gain of EIPR1 function and promotes neural development and vesicle trafficking. Our study provides a powerful framework for identifying regulatory risk variants and contributes to our understanding of the interplay between genetic and epigenetic variants in mediating psychiatric disorder susceptibility.


Assuntos
Metilação de DNA , Proteínas Nucleares/genética , Esquizofrenia , Alelos , Metilação de DNA/genética , Epigênese Genética/genética , Humanos , Regiões Promotoras Genéticas , Esquizofrenia/genética , Gêmeos Monozigóticos/genética
16.
Neurol Sci ; 43(4): 2681-2692, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34647219

RESUMO

BACKGROUND: Suid herpesvirus type 1 (SHV1) is a type of neurotropic virus able to infect various species. However, the clinical cases of human SHV1 encephalitis are still rarely reported, and the clinical characteristics, treatment, and prognosis of human SHV1 encephalitis are still unclear. METHODS: In this study, we reported 2 cases of human encephalitis associated with SHV1 infection and reviewed the other 18 cases from the literatures. A total of 20 cases with human SHV1 encephalitis were summarized and re-analyzed. RESULTS: Nineteen of 20 patients had a history of swine-related occupational exposure before illness onset. All patients initially presented with influenza-like symptoms and then developed seizures, disturbed consciousness, and endophthalmitis. All patients with clinical outcome of modified Rankin Scale of 5 or 6 suffered from rapid progressive respiratory failure. The results of cerebrospinal fluid (CSF) indicated aseptic or viral infection. MRI findings of SHV1 encephalitis were prone to distribute in temporal-frontal and insular cortex, which was similar to the pattern of herpes simplex virus encephalitis, while some cases with involvements of gray matter nuclei had a high rate of mortality. Metagenomic next-generation sequencing (mNGS) revealed that all patients had unique SHV1 sequences with variable reads in the CSF. CONCLUSIONS: The variant SHV1 can cause a new type of human viral encephalitis, characterized by acute, fulminating, and catastrophic central nervous system infection. Rapid progressive respiratory failure and extensive lesions of deep gray matter nuclei might be indicators to poor prognosis. No approved treatments for the encephalitis are available, but it is possible to diagnose encephalitis quickly by mNGS.


Assuntos
Encefalite por Herpes Simples , Encefalite Viral , Herpesvirus Humano 1 , Herpesvirus Suídeo 1 , Animais , Encefalite por Herpes Simples/diagnóstico , Encefalite Viral/diagnóstico , Herpesvirus Humano 3 , Humanos , Imageamento por Ressonância Magnética , Suínos
17.
Tohoku J Exp Med ; 256(2): 141-150, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35185081

RESUMO

Glioma is the most common tumor of central nervous system in adults with poor prognosis. Yippee Like 1 (YPEL1) is a newly discovered protein that plays contradictory roles in pancreatic cancer and colon cancer. Here we initially explored the expression, clinical significance, and function of YPEL1 in glioma. The transcription level of YPEL1 in glioma patients was extracted from TCGA datasets via GEPIA website. As a result, the mRNA level of YPEL1 was significantly lower in glioma tissues than that in normal brain tissues. Immunohistochemistry staining was next conducted to test protein expression of YPEL1 in glioma tissues (n = 130). Consistently, lower protein expression of YPEL1 was observed in cases with larger tumor size and advanced WHO grades. Univariate and multivariate analyses identified YPEL1 as a novel independent prognostic factor of gliomas. Finally, overexpression of YPEL1 was performed in U87 and U373 cell lines to further validate its tumor-related functions, followed by proliferation, invasion, and subcutaneous mice xenografts assays. In vitro and in vivo data demonstrated that overexpressing YPEL1 can remarkably prevent glioma cell proliferation and invasion. Taken together, our data revealed that low YPEL1 expression was significantly correlated with poor overall survival of glioma patients and may play anti-tumor effects.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Pancreáticas , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Humanos , Imuno-Histoquímica , Camundongos , Neoplasias Pancreáticas/genética , Prognóstico
18.
Chaos ; 32(4): 043110, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35489847

RESUMO

We uncover a phenomenon in coupled nonlinear networks with a symmetry: as a bifurcation parameter changes through a critical value, synchronization among a subset of nodes can deteriorate abruptly, and, simultaneously, perfect synchronization emerges suddenly among a different subset of nodes that are not directly connected. This is a synchronization metamorphosis leading to an explosive transition to remote synchronization. The finding demonstrates that an explosive onset of synchrony and remote synchronization, two phenomena that have been studied separately, can arise in the same system due to symmetry, providing another proof that the interplay between nonlinear dynamics and symmetry can lead to a surprising phenomenon in physical systems.

19.
Chaos ; 32(9): 093132, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36182361

RESUMO

Symmetries, due to their fundamental importance to dynamical processes on networks, have attracted a great deal of current research. Finding all symmetric nodes in large complex networks typically relies on automorphism groups from algebraic-group theory, which are solvable in quasipolynomial time. We articulate a conceptually appealing and computationally extremely efficient approach to finding and characterizing all symmetric nodes by introducing a structural position vector (SPV) for each node in networks. We establish the mathematical result that symmetric nodes must have the same SPV value and demonstrate, using six representative complex networks from the real world, that all symmetric nodes in these networks can be found in linear time. Furthermore, the SPVs not only characterize the similarity of nodes but also quantify the nodal influences in propagation dynamics. A caveat is that the proved mathematical result relating the SPV values to nodal symmetries is not sufficient; i.e., nodes having the same SPV values may not be symmetric, which arises in regular networks or networks with a dominant regular component. We point out with an analysis that this caveat is, in fact, shared by the known existing approaches to finding symmetric nodes in the literature. We further argue, with the aid of a mathematical analysis, that our SPV method is generally effective for finding the symmetric nodes in real-world networks that typically do not have a dominant regular component. Our SPV-based framework, therefore, provides a physically intuitive and computationally efficient way to uncover, understand, and exploit symmetric structures in complex networks arising from real-world applications.

20.
Heart Surg Forum ; 25(1): E053-E055, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35238317

RESUMO

BACKGROUND: Scapulothoracic dissociation (STD) is a rare, life-threatening injury, usually resulting from high energy and leading to poor clinical outcomes and high incidence of disability. This case and a review of the literature aimed to highlight the early diagnosis and management of STD. CASE PRESENTATION: A 61-year-old man was injured in a motorcycle accident, when he took a sudden turn and fell from his motorcycle. He was admitted to the emergency department of Changsha Central Hospital. Based on the computed tomography (CT) and digital subtraction angiogram (DSA) findings, the patient was diagnosed as follows: right scapulothoracic dislocation syndrome, right subclavian artery rupture, right subclavian vein rupture, right clavicular fracture, right multiple rib fractures, and right lung contusion and laceration. An expanded polytetrafluoroethylene interposition graft was implemented in the right subclavian artery to re-establish continuity of the subclavian artery. Surgery was performed to repair thoracic deformity, and active rehabilitation therapy also was implemented after surgery. The patient was discharged from the hospital and recovered well with grade 4 muscle strength in his right arm. CONCLUSIONS: Physicians should be vigilant for STD in all patients with shoulder girdle injury. DSA could be recommended for patients with unstable hemodynamics. Early diagnostic image tests and individualized management should be implemented, according to the patient's condition.


Assuntos
Fraturas Ósseas , Artéria Subclávia , Tronco Braquiocefálico , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Tomografia Computadorizada por Raios X
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