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1.
Nature ; 623(7987): 608-615, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938768

RESUMO

Cell therapies have yielded durable clinical benefits for patients with cancer, but the risks associated with the development of therapies from manipulated human cells are understudied. For example, we lack a comprehensive understanding of the mechanisms of toxicities observed in patients receiving T cell therapies, including recent reports of encephalitis caused by reactivation of human herpesvirus 6 (HHV-6)1. Here, through petabase-scale viral genomics mining, we examine the landscape of human latent viral reactivation and demonstrate that HHV-6B can become reactivated in cultures of human CD4+ T cells. Using single-cell sequencing, we identify a rare population of HHV-6 'super-expressors' (about 1 in 300-10,000 cells) that possess high viral transcriptional activity, among research-grade allogeneic chimeric antigen receptor (CAR) T cells. By analysing single-cell sequencing data from patients receiving cell therapy products that are approved by the US Food and Drug Administration2 or are in clinical studies3-5, we identify the presence of HHV-6-super-expressor CAR T cells in patients in vivo. Together, the findings of our study demonstrate the utility of comprehensive genomics analyses in implicating cell therapy products as a potential source contributing to the lytic HHV-6 infection that has been reported in clinical trials1,6-8 and may influence the design and production of autologous and allogeneic cell therapies.


Assuntos
Linfócitos T CD4-Positivos , Herpesvirus Humano 6 , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Ativação Viral , Latência Viral , Humanos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Ensaios Clínicos como Assunto , Regulação Viral da Expressão Gênica , Genômica , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/isolamento & purificação , Herpesvirus Humano 6/fisiologia , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Encefalite Infecciosa/complicações , Encefalite Infecciosa/virologia , Receptores de Antígenos Quiméricos/imunologia , Infecções por Roseolovirus/complicações , Infecções por Roseolovirus/virologia , Análise da Expressão Gênica de Célula Única , Carga Viral
2.
J Phys Chem A ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109870

RESUMO

This study elucidates the mechanisms and principles governing chemoselectivity in synthesizing two distinct N-heterocycles, benzimidazole thiazine and benzothiazole imidazole, through BF3•OEt2-catalyzed cyclization reactions of propargyl alcohols with benzimidazole thiols. Employing density functional theory calculations, we highlight the crucial role of fluorine source in influencing chemoselectivity. In DCM, BF3, as the catalytic center, coordinates with propargyl alcohol's hydroxyl group to form a precursor. Conversely, in DMF, [BF2•DMF]+, formed from DMF and BF3•OEt2, acts as the catalytic center, activating the propargyl alcohol's hydroxyl group. The mechanisms in both solvents involve sequential steps: B-O bond formation, C-O bond cleavage, S-C bond formation, hydrogen atom transfer (HAT), cyclization, and deprotonation. A notable difference is the HAT process: in DCM, it follows a 1,5-HAT process, while in DMF, BF4- formation from DMF and BF3•OEt2 provides a fluorine source and introduces steric hindrance, favoring a 1,6-HAT process and leading to unique chemoselectivity. This pioneering research showcases the impact of DMF on cyclization reactions, offering valuable insights for comprehending and designing reactions driven by fluorine sources. Crucially, our results propose an innovative reaction mechanism featuring lower potential energy surfaces, enhancing our understanding of the intricate interplay among reactants, catalysts, and solvents.

3.
Chin J Traumatol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637176

RESUMO

PURPOSE: Traumatic brain injury (TBI), currently a major global public health problem, imposes a significant economic burden on society and families. We aimed to quantify and predict the incidence and severity of TBI by analyzing its incidence, prevalence, and years lived with disability (YLDs). The epidemiological changes in TBI from 1990 to 2019 were described and updated to provide a reference for developing prevention, treatment, and incidence-reducing measures for TBI. METHODS: A secondary analysis was performed on the incidence, prevalence, and YLDs of TBI by sex, age group, and region (n = 21,204 countries and territories) between 1990 and 2019 using the Global Burden of Diseases, Injuries, and Risk Factors Study 2019. Proportions in the age-standardized incidence rate due to underlying causes of TBI and proportions of minor and moderate or severe TBI were also reported. RESULTS: In 2019, there were 27.16 million (95% uncertainty intervals (UI): 23.36 - 31.42) new cases of TBI worldwide, with age-standardized incidence and prevalence rates of 346 per 100,000 population (95% UI: 298-401) and 599 per 100,000 population (95% UI: 573-627), respectively. From 1990 to 2019, there were no significant trends in global age-standardized incidence (estimated annual percentage changes: -0.11%, 95% UI: -0.18% - -0.04%) or prevalence (estimated annual percentage changes: 0.01%, 95% UI: -0.04% - 0.06%). TBI caused 7.08 million (95% UI: 5.00 - 9.59) YLDs in 2019, with age-standardized rates of 86.5 per 100,000 population (95% UI: 61.1 - 117.2). In 2019, the countries with higher incidence rates were mainly distributed in Central Europe, Eastern Europe, and Australia. The 2019 global age-standardized incidence rate was higher in males than in females. The 2019 global incidence of moderate and severe TBI was 182.7 per 100,000 population, accounting for 52.8% of all TBI, with falls and road traffic injuries being the main causes in most regions. CONCLUSIONS: The incidence of moderate and severe TBI was slightly higher in 2019, and TBI still accounts for a significant portion of the global injury burden. The likelihood of moderate to severe TBI and the trend of major injury under each injury cause from 1990 to 2019 and the characteristics of injury mechanisms in each age group are presented, providing a basis for further research on injury causes in each age group and the future establishment of corresponding policies and protective measures.

4.
J Am Chem Soc ; 144(1): 339-348, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34935377

RESUMO

A copper-catalyzed remote benzylic C-H functionalization strategy enabling 1,2-difunctionalization of alkenes with 2-methylbenzeneamides and nucleophiles, including alcohols, indoles, pyrroles, and the intrinsic amino groups, is reported, which is characterized by its redox-neutral conditions, exquisite site-selectivity, broad substrate scope, and wide utilizations of late-stage modifying bioactive molecules. This reaction proceeds through nitrogen-centered radical generation, hydrogen atom transfer, benzylic radical addition across the alkenes, single-electron oxidation, and carbocation electrophilic course cascades. While using external nucleophiles manipulates three-component alkene alkylalkoxylation and alkyl-heteroarylation with 2-methylbenzeneamides to access dialkyl ethers, 3-alkylindoles, and 3-alkylpyrroles, omitting the external nucleophiles results in two-component alkylamidation ([5+2] annulation) of alkenes with 2-methylbenzeneamides to benzo-[f][1,2]thiazepine 1,1-dioxides.

5.
Org Biomol Chem ; 18(11): 2170-2174, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32140694

RESUMO

A copper-catalyzed C-H [3 + 2] annulation of N-substituted anilines with α-carbonyl alkyl bromides for the synthesis of 3,3'-disubstituted oxindoles is developed. Tandem C-H cycloamidation reactions of various α-carbonyl alkyl bromide derivatives including tertiary-α-bromoalkyl ketone esters, malonic esters and cycloalkanes, with N-aryl or alkyl substituted anilines, can be performed using this system, affording a vast array of valuable 3,3'-disubstituted oxindoles in moderate to good yields.

6.
Org Biomol Chem ; 18(25): 4843-4847, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32608447

RESUMO

A simple and practical method for the synthesis of phosphoryl-substituted indolo[2,1-a]isoquinolin-6(5H)-ones and benzimidazo[2,1-a]isoquinolin-6(5H)-ones through manganese(iii)-promoted tandem phosphinoylation/cyclization of 2-arylindoles or 2-arylbenzimidazoles with disubstituted phosphine oxides was developed. In this transformation, new C-P bond and C-C bond were constructed simultaneously under silver-free conditions, exhibiting a broad substrate scope. It was noted that not only diarylphosphine oxides but also dialkyl and arylalkyl-phosphine oxides were compatible with the conditions.

7.
Chem Rec ; 19(2-3): 440-451, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30033609

RESUMO

Functionalization of alkenes has been well investigated by chemists, thus it has been extensively applied in organic synthesis and industries. In the past few decades, transition-metal, such as palladium, rhodium, gold, iridium, copper and iron, catalyzed functionalization reactions of alkenes have been significantly developed and played vital roles in synthesis. The difunctionalization of alkenes are appealing as an important alternative to the traditional approaches for the construction of useful carbon centers, particularly carbon quaternary centers, which commonly existed as structural motifs in numerous natural products, pharmaceuticals, and biologically active molecules. This account will summarize our recent advances in the intermolecular difunctionalization of alkenes, and also highlight the scope and limitations as well as the mechanisms of these difunctionalization reactions. In general, in this account the difunctionalization of alkenes starting from dicarbofunctionalization will be discussed. Then carboheterofunctionalization of alkenes will be intensively reviewed, and diheterofunctionalization will also be highlighted.

8.
Angew Chem Int Ed Engl ; 57(40): 13308-13312, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30114326

RESUMO

A new palladium-catalyzed reductive [5+1] cycloaddition of 3-acetoxy-1,4-enynes with CO, enabled by hydrosilanes, has been developed for delivering valuable functionalized phenols. This methodology employs hydrosilanes as the external reagent to facilitate the [5+1] carbonylative benzannulation. The reaction is a conceptually and mechanistically novel carbonylative cycloaddition route for the construction of substituted phenols, through the formation of four new chemical bonds, with excellent functional-group tolerance.

9.
Angew Chem Int Ed Engl ; 56(27): 7916-7919, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28488789

RESUMO

The first iron-catalyzed 1,2-difunctionalization of styrenes and conjugated alkenes with silanes and either N or C, using an oxidative radical strategy, is described. Employing FeCl2 and di-tert-butyl peroxide allows divergent alkene 1,2-difunctionalizations, including 1,2-aminosilylation, 1,2-arylsilylation, and 1,2-alkylsilylation, which rely on a wide range of nucleophiles, namely, amines, amides, indoles, pyrroles, and 1,3-dicarbonyls, thus providing a powerful platform for producing diverse silicon-containing alkanes.

10.
J Org Chem ; 81(16): 7148-54, 2016 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-27377434

RESUMO

A new intermolecular 1,2-alkylarylation of styrenes with α-carbonyl alkyl bromides and indoles using fac-[Ir(ppy)3] as the photoredox catalyst has been developed. The method allows the simultaneous formation of two new carbon-carbon bonds through three component reaction, and represents a new single-electron transfer (SET) strategy for the 1,2-alkylarylation of the styrenes with broad substrate scope and excellent functional group tolerance.

11.
Anim Biotechnol ; 27(1): 1-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26485397

RESUMO

A proliferation-inducing ligand (APRIL) is a critical member of the tumor necrosis factor (TNF) superfamily, which is involved in immune regulation. In the present study, the cDNA of cat APRIL (cAPRIL) was successfully amplified. Sequence analysis showed that the open reading frame (ORF) of cAPRIL contains a putative furin protease cleavage site (R-R-K-R), a conserved putative N-glycosylation site (Asn(124)), and two conservative cysteine residues (Cys(196) and Cys(211)). Real-time quantitative PCR (qPCR) analysis revealed that cAPRIL could be detected in various tissues. The phylogenetic analysis and predicted three dimensional (3D) structure revealed that it is similar to its counterparts. The extracellular soluble domain of the cAPRIL (csAPRIL) fragment was cloned into the expression vector pET43.1a. SDS-PAGE and Western blotting analysis indicated a high-level expression of csAPRIL protein in Escherichia coli BL21 (DE3). MTT assays revealed that purified recombinant csAPRIL protein was able to stimulate proliferation of mouse B-cells. These findings indicate that cAPRIL plays an important role in proliferation of B-cells and provide the basis for investigation on the roles of APRIL in this important domestic species.


Assuntos
Gatos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Sequência de Aminoácidos , Animais , Linfócitos B/efeitos dos fármacos , Sequência de Bases , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Escherichia coli/genética , Masculino , Camundongos , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/química , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/farmacologia
12.
Angew Chem Int Ed Engl ; 55(9): 3187-91, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26823074

RESUMO

A new iron-facilitated silver-mediated radical 1,2-alkylarylation of styrenes with α-carbonyl alkyl bromides and indoles is described, and two new C-C bonds were generated in a single step through a sequence of intermolecular C(sp(3)-Br functionalization and C(sp(2))-H functionalization across the alkenes. This method provides an efficient access to alkylated indoles with broad substrate scope and excellent selectivity.

13.
Angew Chem Int Ed Engl ; 55(35): 10423-6, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27457771

RESUMO

A new FeCl3 and BF3 ⋅OEt2 co-catalyzed tandem hetero-[5+2] cycloaddition of 2-(2-aminoethyl)oxiranes with a wide range of alkynes, including terminal alkynes and alkyl-substituted internal alkynes is presented. This is the first example of rapid and facile production of diverse 2,3-dihydro-1H-azepines through a sequence of epoxide ring-opening, annulation, and dehydroxylation with broad substrate scope and exquisite selectivity control.

14.
Proteomics ; 15(12): 1943-56, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25764121

RESUMO

Viruses are intracellular parasites that can only replicate and spread in cells of susceptible hosts. Alpha herpesviruses (α-HVs) contain double-stranded DNA genomes of at least 120 kb, encoding for 70 or more genes. The viral genome is contained in an icosahedral capsid that is surrounded by a proteinaceous tegument layer and a lipid envelope. Infection starts in epithelial cells and spreads to the peripheral nervous system. In the natural host, α-HVs establish a chronic latent infection that can be reactivated and rarely spread to the CNS. In the nonnatural host, viral infection will in most cases spread to the CNS with often fatal outcome. The host response plays a crucial role in the outcome of viral infection. α-HVs do not encode all the genes required for viral replication and spread. They need a variety of host gene products including RNA polymerase, ribosomes, dynein, and kinesin. As a result, the infected cell is dramatically different from the uninfected cell revealing a complex and dynamic interplay of viral and host components required to complete the virus life cycle. In this review, we describe the pivotal contribution of MS-based proteomics studies over the past 15 years to understand the complicated life cycle and pathogenesis of four α-HV species from the alphaherpesvirinae subfamily: Herpes simplex virus-1, varicella zoster virus, pseudorabies virus and bovine herpes virus-1. We describe the viral proteome dynamics during host infection and the host proteomic response to counteract such pathogens.


Assuntos
Alphaherpesvirinae/fisiologia , Infecções por Herpesviridae/metabolismo , Interações Hospedeiro-Patógeno , Espectrometria de Massas/métodos , Proteoma/análise , Proteômica/métodos , Proteínas Virais/metabolismo , Animais , Bovinos , Infecções por Herpesviridae/virologia , Replicação Viral
15.
Yi Chuan ; 37(4): 367-373, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25881702

RESUMO

Human NKX2.5 (NK2 homeobox 5) premature stop codon (PTC) mutations cause congenital heart diseases such as atrial septal defect and atrioventricular block. At present, eight NKX2.5 PTC mutations were reported as E109X, Q149X, Q170X, Q187X, Q198X, Y256X, Y259X and C264X. To observe the ability of tRNA suppressors to read through NKX2.5 PTC mutations and produce functional full-length proteins, eight NKX2.5 PTC mutations were cloned into pcDNA3.1(-) vectors and four fragments (wild-type NKX2.5, E109X, Q149X and C264X) were cloned in pEGFP-N1 vectors to acquire NKX2.5-EGFP fusing plasmids. After transfection of NKX2.5-EGFP with or without corresponding tRNA suppressor into HeLa cells, the quantity of EGFP was measured to confirm the readthrough ability of the PTCs. NKX2.5 full-length and truncated protein expression levels were examined by Western blotting and the readthrough efficiency of tRNA suppressors on the PTCs was calculated respectively. The activity of NKX2.5 full-length and truncated protein was confirmed on NKX2.5 target gene-Cx43 mRNA level measured by Real-time PCR. Three tRNA suppressors were used: tRNA am, tRNA oc and tRNA op. tRNA am could suppress UAG-containing PTCs Q149X, Q170X, Q187X, Q198X and the readthrough efficiency for the latter three was above 50%. tRNA op could suppress UGA-containing PTC C264X with ~50% readthrough efficiency. tRNA oc failed to read through NKX2.5 PTC mutations. The relative Cx43 mRNA level in all readthrough samples was increased to 7%-41.7%. In conclusion, tRNA am and tRNA op could suppress NKX2.5 PTCs and induce functional protein expression. However, the effects of tRNA suppressors on cellular function are not clear yet, warranting further researches.


Assuntos
Códon de Terminação/genética , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Terminação Traducional da Cadeia Peptídica , RNA de Transferência/genética , Fatores de Transcrição/genética , Códon de Terminação/metabolismo , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/metabolismo , Humanos , RNA de Transferência/metabolismo , Fatores de Transcrição/metabolismo
16.
Angew Chem Int Ed Engl ; 54(2): 608-12, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25411014

RESUMO

A new metal-free radical 5-exo-dig cyclization of phenol-linked 1,6-enynes with O2, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), and tBuONO is described. With this general method, carbonylated benzofurans can be accessed through incorporation of two oxygen atoms into the product from O2 and TEMPO through dioxygen activation and oxidative cleavage of the N-O bond, respectively.


Assuntos
Benzofuranos/síntese química , Metais/química , Fenóis/química , Ciclização
17.
Angew Chem Int Ed Engl ; 54(22): 6595-9, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25872912

RESUMO

A rhodium(III)-catalyzed [3+2]/[5+2] annulation of 4-aryl 1-tosyl-1,2,3-triazoles with internal alkynes is presented. This transformation provides straightforward access to indeno[1,7-cd]azepine architectures through a sequence involving the formation of a rhodium(III) azavinyl carbene, dual C(sp(2))-H functionalization, and [3+2]/[5+2] annulation.


Assuntos
Alcinos/química , Ródio/química , Triazóis/química , Azepinas/química , Carbono/química , Catálise , Reação de Cicloadição , Hidrogênio/química
18.
Angew Chem Int Ed Engl ; 54(33): 9577-80, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26119085

RESUMO

A new metal-free oxidative radical [2+2+1] carbocyclization of benzene-linked 1,n-enynes with two C(sp(3))-H bonds adjacent to the same heteroatom is described. This method achieves two C(sp(3))-H oxidative functionalizations and an annulation, thus providing efficient and general access to a variety of fused five-membered carbocyclic hydrocarbons.


Assuntos
Derivados de Benzeno/química , Radicais Livres/química , Compostos Heterocíclicos/química , Peróxidos/química , Catálise , Ciclização , Oxirredução
19.
Eur J Immunol ; 43(4): 1034-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23322406

RESUMO

Ag receptor engagement triggers lymphocyte activation and proliferation by activating several transcription factors including NF-κB. Caspase recruitment domain (CARD) containing membrane-associated guanylate kinase (MAGUK) protein 1 (CARMA1) is an essential adaptor protein that links Ag receptors to NF-κB activation. Here, we identify stress-induced-phosphoprotein 1 homology and U-box containing protein 1 (STUB1) as a CARMA1-associated protein. STUB1 constitutively interacted with CARMA1, and the interaction was intensified by TCR stimulation. Downregulation of STUB1 expression by RNAi markedly diminished TCR-induced canonical NF-κB activation and IL-2 production. Furthermore, overexpression of STUB1 enhanced the ubiquitination of CARMA1, whereas knockdown of STUB1 abolished the endogenous ubiquitination of CARMA1 induced by TCR stimulation. Subsequently, the ubiquitination of CARMA1 catalyzed by STUB1 was identified as Lys-27 linked, which is important for CARMA1-mediated NF-κB activation. These data provide the first evidence that ubiquitination of CARMA1 by STUB1 promotes TCR-induced NF-κB signaling.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Guanilato Ciclase/metabolismo , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Catálise , Linhagem Celular , Ativação Enzimática , Humanos , Interleucina-2/biossíntese , NF-kappa B/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
20.
Chemistry ; 20(7): 1843-6, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24488954

RESUMO

A mild and general alkylation of terminal alkynes with transient σ-alkylpalladium(II) complexes for assembling alkyl-substituted alkynes is described. This method represents a new way to the use of transient σ-alkylpalladium(II) complexes in organic synthesis through 1,2-carboalkynylation of alkenes.


Assuntos
Alcinos/química , Complexos de Coordenação/química , Paládio/química , Alcenos/química , Alquilação
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