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1.
J Am Chem Soc ; 146(10): 6936-6946, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38414423

RESUMEN

Here, we describe a cooperative Pd(0)/chiral phosphoric acid catalytic system that allows us to realize the first chemo-, regio-, and enantioselective sequential cross-[4 + 2]-cycloaddition/decarboxylation reaction between 2-pyrones and unactivated acyclic 1,3-dienes. The key to the success of this transformation is the utilization of an achiral N-heterocyclic carbene (NHC) as the ligand and a newly developed chiral phosphoric acid as the cocatalyst. Experimental investigations and computational studies support the idea that the Pd(0)/NHC complex acts as a π-Lewis base to increase the nucleophilicity of 1,3-dienes via η2 coordination, while the chiral phosphoric acid simultaneously increases the electrophilicity of 2-pyrones by hydrogen bonding. By this synergistic catalysis, the sequential cross-[4 + 2]-cycloaddition and decarboxylation reaction proceeds efficiently, enabling the preparation of a wide range of chiral vinyl-substituted 1,3-cyclohexadienes in good yields and enantioselectivities. The synthetic utility of this reaction is demonstrated by synthetic transformations of the product to various valuable chiral six-membered carbocycles.

2.
Respir Res ; 25(1): 186, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678295

RESUMEN

BACKGROUND: Influenza A viruses (IAV) are extremely common respiratory viruses for the acute exacerbation of chronic obstructive pulmonary disease (AECOPD), in which IAV infection may further evoke abnormal macrophage polarization, amplify cytokine storms. Melatonin exerts potential effects of anti-inflammation and anti-IAV infection, while its effects on IAV infection-induced AECOPD are poorly understood. METHODS: COPD mice models were established through cigarette smoke exposure for consecutive 24 weeks, evaluated by the detection of lung function. AECOPD mice models were established through the intratracheal atomization of influenza A/H3N2 stocks in COPD mice, and were injected intraperitoneally with melatonin (Mel). Then, The polarization of alveolar macrophages (AMs) was assayed by flow cytometry of bronchoalveolar lavage (BAL) cells. In vitro, the effects of melatonin on macrophage polarization were analyzed in IAV-infected Cigarette smoking extract (CSE)-stimulated Raw264.7 macrophages. Moreover, the roles of the melatonin receptors (MTs) in regulating macrophage polarization and apoptosis were determined using MTs antagonist luzindole. RESULTS: The present results demonstrated that IAV/H3N2 infection deteriorated lung function (reduced FEV20,50/FVC), exacerbated lung damages in COPD mice with higher dual polarization of AMs. Melatonin therapy improved airflow limitation and lung damages of AECOPD mice by decreasing IAV nucleoprotein (IAV-NP) protein levels and the M1 polarization of pulmonary macrophages. Furthermore, in CSE-stimulated Raw264.7 cells, IAV infection further promoted the dual polarization of macrophages accompanied with decreased MT1 expression. Melatonin decreased STAT1 phosphorylation, the levels of M1 markers and IAV-NP via MTs reflected by the addition of luzindole. Recombinant IL-1ß attenuated the inhibitory effects of melatonin on IAV infection and STAT1-driven M1 polarization, while its converting enzyme inhibitor VX765 potentiated the inhibitory effects of melatonin on them. Moreover, melatonin inhibited IAV infection-induced apoptosis by suppressing IL-1ß/STAT1 signaling via MTs. CONCLUSIONS: These findings suggested that melatonin inhibited IAV infection, improved lung function and lung damages of AECOPD via suppressing IL-1ß/STAT1-driven macrophage M1 polarization and apoptosis in a MTs-dependent manner. Melatonin may be considered as a potential therapeutic agent for influenza virus infection-induced AECOPD.


Asunto(s)
Apoptosis , Subtipo H3N2 del Virus de la Influenza A , Melatonina , Enfermedad Pulmonar Obstructiva Crónica , Animales , Melatonina/farmacología , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/virología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ratones , Apoptosis/efectos de los fármacos , Células RAW 264.7 , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/inmunología , Ratones Endogámicos C57BL , Masculino , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Progresión de la Enfermedad , Polaridad Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virología
3.
J Nanobiotechnology ; 22(1): 66, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38368393

RESUMEN

BACKGROUND: The transplantation of exosomes derived from human adipose-derived mesenchymal stem cells (hADSCs) has emerged as a prospective cellular-free therapeutic intervention for the treatment of neurodevelopmental disorders (NDDs), as well as autism spectrum disorder (ASD). Nevertheless, the efficacy of hADSC exosome transplantation for ASD treatment remains to be verified, and the underlying mechanism of action remains unclear. RESULTS: The exosomal long non-coding RNAs (lncRNAs) from hADSC and human umbilical cord mesenchymal stem cells (hUCMSC) were sequenced and 13,915 and 729 lncRNAs were obtained, respectively. The lncRNAs present in hADSC-Exos encompass those found in hUCMSC-Exos and are associated with neurogenesis. The biodistribution of hADSC-Exos in mouse brain ventricles and organoids was tracked, and the cellular uptake of hADSC-Exos was evaluated both in vivo and in vitro. hADSC-Exos promote neurogenesis in brain organoid and ameliorate social deficits in ASD mouse model BTBR T + tf/J (BTBR). Fluorescence in situ hybridization (FISH) confirmed lncRNA Ifngas1 significantly increased in the prefrontal cortex (PFC) of adult mice after hADSC-Exos intraventricular injection. The lncRNA Ifngas1 can act as a molecular sponge for miR-21a-3p to play a regulatory role and promote neurogenesis through the miR-21a-3p/PI3K/AKT axis. CONCLUSION: We demonstrated hADSC-Exos have the ability to confer neuroprotection through functional restoration, attenuation of neuroinflammation, inhibition of neuronal apoptosis, and promotion of neurogenesis both in vitro and in vivo. The hADSC-Exos-derived lncRNA IFNG-AS1 acts as a molecular sponge and facilitates neurogenesis via the miR-21a-3p/PI3K/AKT signaling pathway, thereby exerting a regulatory effect. Our findings suggest a potential therapeutic avenue for individuals with ASD.


Asunto(s)
Trastorno del Espectro Autista , Exosomas , Células Madre Mesenquimatosas , MicroARNs , ARN Largo no Codificante , Humanos , Ratones , Animales , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Exosomas/metabolismo , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/terapia , Trastorno del Espectro Autista/metabolismo , Hibridación Fluorescente in Situ , Fosfatidilinositol 3-Quinasas/metabolismo , Estudios Prospectivos , Distribución Tisular , Neurogénesis , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Mesenquimatosas/metabolismo , Interferón gamma/metabolismo
4.
Cancer Cell Int ; 23(1): 129, 2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37394466

RESUMEN

BACKGROUND: The gefitinib resistance mechanism in non-small cell lung cancer (NSCLC) remains unclear, albeit exosomal circular RNA (circRNA) is known to possibly play a vital role in it. METHODS: We employed high-throughput sequencing techniques to detect the expressions of exosomal circRNA both in gefitinib-resistant and gefitinib-sensitive cells in this study. The circKIF20B expression was determined in serum exosomes and tissues of patients by qRT-PCR. The structure, stability, and intracellular localization of circKIF20B were verified by Sanger sequencing, Ribonuclease R (RNase R)/actinomycin D (ACTD) treatments, and Fluorescence in situ hybridization (FISH). The functions of circKIF20B were investigated by 5-Ethynyl-20-deoxyuridine (EdU), flow cytometry, Cell Counting Kit-8 (CCK-8), oxygen consumption rate (OCR), and xenograft model. Co-culture experiments were performed to explore the potential ability of exosomal circKIF20B in treating gefitinib resistance. The downstream targets of circKIF20B were determined by luciferase assay, RNA pulldown, and RNA immunoprecipitation (RIP). RESULTS: We found that circKIF20B was poorly expressed in the serum exosomes of gefitinib-resistant patients (n = 24) and the tumor tissues of patients with NSCLC (n = 85). CircKIF20B was negatively correlated with tumor size and tumor stage. Decreasing circKIF20B was found to promote gefitinib resistance by accelerating the cell cycle, inhibiting apoptosis, and enhancing mitochondrial oxidative phosphorylation (OXPHOS), whereas increasing circKIF20B was found to restore gefitinib sensitivity. Mechanistically, circKIF20B is bound to miR-615-3p for regulating the MEF2A and then altering the cell cycle, apoptosis, and mitochondrial OXPHOS. Overexpressing circKIF20B parental cells can restore sensitivity to gefitinib in the recipient cells by upregulating the exosomal circKIF20B expression. CONCLUSIONS: This study revealed a novel mechanism of circKIF20B/miR-615-3p/MEF2A signaling axis involving progression of gefitinib resistance in NSCLC. Exosomal circKIF20B is expected to be an easily accessible and alternative liquid biopsy candidate and potential therapeutic target in gefitinib-resistant NSCLC. The schematic diagram of mechanism in this study. Exosomal circKIF20B inhibits gefitinib resistance and cell proliferation by arresting the cell cycle, promoting apoptosis, and reducing OXPHOS via circKIF20B/miR-615-3p/MEF2A axis in NSCLC.

5.
Hum Genomics ; 16(1): 41, 2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-36123719

RESUMEN

BACKGROUND: Heterotaxy syndrome (HTX) is caused by aberrant left-right patterning early in embryonic development, which results in abnormal positioning and morphology of the thoracic and abdominal organs. Currently, genetic testing discerns the underlying genetic cause in less than 20% of sporadic HTX cases, indicating that genetic pathogenesis remains poorly understood. In this study, we aim to garner a deeper understanding of the genetic factors of this disease by documenting the effect of different matrix metalloproteinase 21 (MMP21) variants on disease occurrence and pathogenesis. METHODS: Eighty-one HTX patients with complex congenital heart defects and 89 healthy children were enrolled, and we investigated the pathogenetic variants related to patients with HTX by exome sequencing. Zebrafish splice-blocking Morpholino oligo-mediated transient suppression assays were performed to confirm the potential pathogenicity of missense variants found in these patients with HTX. RESULTS: Three MMP21 heterozygous non-synonymous variants (c.731G > A (p.G244E), c.829C > T (p.L277F), and c.1459A > G (p.K487E)) were identified in three unrelated Chinese Han patients with HTX and complex congenital heart defects. Sanger sequencing confirmed that all variants were de novo. Cell transfection assay showed that none of the variants affect mRNA and protein expression levels of MMP21. Knockdown expression of mmp21 by splice-blocking Morpholino oligo in zebrafish embryos revealed a heart looping disorder, and mutant human MMP21 mRNA (c.731G > A, c.1459A > G, heterozygous mRNA (wild-type&c.731G > A), as well as heterozygous mRNA (wild-type& c.1459A > G) could not effectively rescue the heart looping defects. A patient with the MMP21 p.G244E variant was identified with other potential HTX-causing missense mutations, whereas the patient with the MMP21 p.K487E variant had no genetic mutations in other causative genes related to HTX. CONCLUSION: Our study highlights the role of the disruptive heterozygous MMP21 variant (p.K487E) in the etiology of HTX with complex cardiac malformations and expands the current mutation spectrum of MMP21 in HTX.


Asunto(s)
Síndrome de Heterotaxia , Animales , Niño , China , Síndrome de Heterotaxia/genética , Humanos , Morfolinos , ARN Mensajero , Factores de Riesgo , Pez Cebra/genética
6.
Angew Chem Int Ed Engl ; 62(32): e202303876, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37286494

RESUMEN

Herein, we show that the combination of the Birch reduction of readily available anisole derivatives and the catalytic asymmetric inverse-electron-demand Diels-Alder reaction of 2-pyrones can serve as a powerful platform for the diverse synthesis of synthetically important cis-decalin scaffolds. Enabled by a well-modified chiral bis(oxazoline) ligand/CuII complex, a wide range of polysubstituted cis-decalin scaffolds with up to six contiguous stereocenters were generated efficiently. The synthetic potential of this method is demonstrated by the concise synthesis of the sesquiterpene (+)-occidentalol and a key intermediate for seven triterpenes. Mechanistic studies suggest the 1,3-cyclohexadienes formed in situ are the key intermediates, and efficient kinetic resolution occurs when C2- and/or C3-substituted 1,4-cyclohexadienes are utilized as substrates. DFT calculations elucidated that the Diels-Alder reaction proceeds in a stepwise fashion and revealed the origins of the stereoselectivities.

7.
J Am Chem Soc ; 144(50): 22858-22864, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36480794

RESUMEN

We report herein an efficient approach for the enantioselective synthesis of inherently chiral calix[4]arenes via palladium-catalyzed asymmetric intramolecular C-H arylations. Using a chiral bifunctional phosphine-carboxylate ligand, the inherent chirality on macrocyclic scaffolds was induced successfully, from which a wide range of calix[4]arenes with fluorenone motifs were obtained with good yields and excellent enantioselectivities (up to >99% ee). The synthetic utility of this method was demonstrated by diverse transformations of the products, thus substantially expanding the chemical space of chiral calix[4]arenes. Further investigations of photophysical and chiroptical properties revealed that calix[4]arenes bearing two fluorenone moieties displayed remarkable glum values (up to 0.019), highlighting the great potential of inherent chirality in the development of organic optoelectronic materials.


Asunto(s)
Gastrópodos , Poríferos , Animales , Paladio , Estereoisomerismo , Ácidos Carboxílicos , Flores , Catálisis
8.
Acta Pharmacol Sin ; 43(8): 2055-2066, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34907359

RESUMEN

Acute lung injury (ALI) is a common and devastating clinical disorder featured by excessive inflammatory responses. Stimulator of interferon genes (STING) is an indispensable molecule for regulating inflammation and immune response in multiple diseases, but the role of STING in the ALI pathogenesis is not well elucidated. In this study, we explored the molecular mechanisms of STING in regulating lipopolysaccharide (LPS)-induced lung injury. Mice were pretreated with a STING inhibitor C-176 (15, 30 mg/kg, i.p.) before LPS inhalation to induce ALI. We showed that LPS inhalation significantly increased STING expression in the lung tissues, whereas C-176 pretreatment dose-dependently suppressed the expression of STING, decreased the production of inflammatory cytokines including TNF-α, IL-6, IL-12, and IL-1ß, and restrained the expression of chemokines and adhesion molecule vascular cell adhesion protein-1 (VCAM-1) in the lung tissues. Consistently, in vitro experiments conducted in TNF-α-stimulated HMEC-1cells (common and classic vascular endothelial cells) revealed that human STING inhibitor H-151 or STING siRNA downregulated the expression levels of adhesion molecule and chemokines in HMEC-1cells, accompanied by decreased adhesive ability and chemotaxis of immunocytes upon TNF-α stimulation. We further revealed that STING inhibitor H-151 or STING knockdown significantly decreased the phosphorylation of transcription factor STAT1, which subsequently influenced its binding to chemokine CCL2 and adhesive molecule VCAM-1 gene promoter. Collectively, STING inhibitor can alleviate LPS-induced ALI in mice by preventing vascular endothelial cells-mediated immune cell chemotaxis and adhesion, suggesting that STING may be a promising therapeutic target for the treatment of ALI.


Asunto(s)
Lesión Pulmonar Aguda , Proteínas de la Membrana , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/prevención & control , Animales , Adhesión Celular , Quimiocinas/metabolismo , Quimiotaxis , Citocinas/metabolismo , Células Endoteliales/metabolismo , Humanos , Lipopolisacáridos/farmacología , Pulmón/patología , Proteínas de la Membrana/antagonistas & inhibidores , Ratones , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/efectos adversos , Molécula 1 de Adhesión Celular Vascular/metabolismo
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(2): 201-207, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35332718

RESUMEN

The human body is colonized by densely-populated and structurally complex communities of microorganisms. The microbiota interact not only with their host cells, but also with other microbiota. Dual RNA sequencing (Dual RNA-seq) can be used to conduct simultaneous analysis of the dynamic changes of gene expression of two (or more) interactive species, and to obtain thus, through the interaction model diagram, the inter-species regulatory relationship of genes of different species, and hence the interaction mechanism between species. We herein reviewed the application status and development prospects of Dual RNA-seq in the research of intestinal, respiratory, skin and oral microbes. Since the concept of Dual RNA-seq was first introduced, the technology has been applied to a range of infection models. Direct investigation into the dynamic interactions between species at the molecular level will contribute to the better understanding of the physiological changes of pathogens and hosts during the course of infection, and thus help reveal potential new targets or biomarkers. However, the Dual RNA-seq technology is still in its early stage of development, and there are some limitations in the experimental technology. For example, due to the dynamic nature of the interaction between species, there are urgent problems awaiting solutions, such as the optimal experimental conditions, the selection of sampling sites and how to achieve real-time observation. In addition, due to the large amount of bioinformatics data of Dual RNA-seq, further research is needed to explore for ways to process the interaction information quickly and flexibly.


Asunto(s)
Interacciones Huésped-Patógeno , Transcriptoma , Biología Computacional , Interacciones Huésped-Patógeno/genética , Humanos , Análisis de Secuencia de ARN
10.
J Am Chem Soc ; 143(24): 8993-9001, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34106720

RESUMEN

The enantioselective synthesis of axially chiral biaryls by a copper-catalyzed Diels-Alder/retro-Diels-Alder reaction of 2-pyrones with alkynes is reported herein. Using electron-deficient 2-pyrones and electron-rich 1-naphthyl acetylenes as the reaction partners, a broad range of axially chiral biaryl esters are obtained in excellent yields (up to 97% yield) and enantioselectivities (up to >99% ee). DFT calculations reveal the reaction mechanism and provide insights into the origins of the stereoselectivities. The practicality and robustness of this reaction are showcased by gram-scale synthesis. The synthetic utilizations are demonstrated by the amenable transformations of the products.

11.
Angew Chem Int Ed Engl ; 60(51): 26610-26615, 2021 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-34668619

RESUMEN

An inverse-electron-demand Diels-Alder (IEDDA) reaction could complement the conventional normal-electron-demand Diels-Alder reaction in the synthesis of six-membered carbocycles. However, catalytic asymmetric all-carbon-based IEDDA reactions are underdeveloped. Herein, we disclosed a copper-catalyzed asymmetric IEDDA reaction using electron-deficient 3-carboalkoxyl-2-pyrones and electronically unbiased indenes as reactants. This method enables the rapid and enantioselective construction of a wide range of hexahydrofluorenyl bridged-lactone scaffolds. Using this method, asymmetric total syntheses of cephanolides A and B were accomplished.

12.
Angew Chem Int Ed Engl ; 59(48): 21425-21430, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-32798266

RESUMEN

An efficient cascade reaction of tryptamine-derived isocyanides with C,N-cyclic azomethine imines is described. The polycyclic pyrrolo[2,3-c]quinoline derivatives, which benefited from rearrangement process driven by hydrogen bonding, could be directly assembled in moderate to good yields (40-87 %) under metal-free and mild conditions. This transformation involved four new heterocyclic rings formations and uniquely, ring opening of indole as well as ring expansion of C,N-cyclic azomethine imine. Both experimental and DFT studies provided guidance on the in-depth insight into the reaction pathways and hydrogen bonding was identified to lower the free energy barrier in transition states. This work constitutes a rare example of tryptamine-derived isocyanide-based cascade reactions, and potentially could be a powerful synthetic strategy for accessing polycyclic analogues involved in natural products.

13.
Opt Express ; 27(2): 1353-1366, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30696202

RESUMEN

A high-precision inter-satellite velocity measurement method based on two-one-way laser Doppler is presented in this paper. This method's working principle and signal-to-noise ratio's effect under different measurement times of signal on velocity precision are analyzed theoretically. This method is also tested by laboratory experiments and 1 mm/s velocity precision is achieved in 1 ms integrating time. The proposed method potentially contributes to inter-satellite velocity measurement, especially for the relative velocity measurement between two satellites in high dynamic motion and a long distance apart.

14.
J Therm Biol ; 84: 111-120, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31466743

RESUMEN

Temperature influences many physiological processes including antioxidant defense and immunity. The hypothesis that air temperatures has no effects on antioxidant defense and innate immunity in Mongolian gerbils (Meriones unguiculatus) was tested. Thirty-three male gerbils were randomly divided into the 4 °C (n = 11), 23 °C (n = 11) and 32 °C groups (n = 11), in which the treatment course lasted for 27 days. We found that air temperatures had no effects on body mass. At lower temperature, gross energy intake and the masses of most organs were higher, whereas fat free dry carcass and body fat were lower. H2O2 titres increased in liver but decreased in small intestine, and remained unchanged in heart, kidney and testis upon cold exposure. At lower temperature, malonaldehyde (MDA) content was higher in the liver, lower in kidneys and testis, and did not differ in the heart and small intestine. The activities of superoxide dismutase (SOD), total antioxidant capacity (T-AOC) in liver were higher in 4 °C group than 23 °C group, while liver catalase (CAT) activity was lower in the 4 °C group than in the 23 °C group. No significant difference was observed in the activities of SOD, CAT and T-AOC in the heart, kidney, testis and small intestine among the 4 °C, 23 °C and 32 °C groups. As expected, bacteria killing capacity indicating innate immunity, white blood cells and thymus mass were all not affected by air temperatures. Similarly, air temperatures had no effect on the levels of testosterone and corticosterone, both of which were not correlated with innate immunity, H2O2 and MDA levels, the activity of SOD, CAT, and T-AOC in all the detected tissues. In conclusion, air temperature affected antioxidant capacity, but not immune responses or serum concentrations of corticosterone and testosterone. Overall, up-regulation or maintenance of antioxidant defenses and immunity might be an important mechanism for gerbils to survive highly variable temperature.


Asunto(s)
Aclimatación , Gerbillinae/inmunología , Gerbillinae/metabolismo , Animales , Composición Corporal , Catalasa/metabolismo , Corticosterona/sangre , Ingestión de Energía , Peróxido de Hidrógeno/metabolismo , Intestino Delgado/metabolismo , Riñón/metabolismo , Recuento de Leucocitos , Hígado/metabolismo , Masculino , Malondialdehído/metabolismo , Miocardio/metabolismo , Superóxido Dismutasa/metabolismo , Temperatura , Testículo/metabolismo , Testosterona/sangre
15.
Angew Chem Int Ed Engl ; 58(41): 14562-14567, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31339615

RESUMEN

An enantioselective chemical synthesis of arene cis-dihydrodiols has been realized from 2-pyrones through sequential ytterbium-catalyzed asymmetric inverse-electron-demand Diels-Alder (IEDDA) reaction of 2-pyrones and retro-Diels-Alder extrusion of CO2 . By using this strategy, a series of substituted arene cis-dihydrodiols can be obtained efficiently with high enantioselectivity (>99 % ee in many cases). Based on this strategy, efficient and concise asymmetric total syntheses of (+)-MK7607 and 1-epi-(+)-MK7607 were accomplished.

16.
BMC Dev Biol ; 18(1): 7, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587629

RESUMEN

BACKGROUND: FK506-binding proteins (FKBPs) have become the subject of considerable interest in several fields, leading to the identification of several cellular and molecular pathways in which FKBPs impact prenatal development and pathogenesis of many human diseases. MAIN BODY: This analysis revealed differences between how mammalian and Drosophila FKBPs mechanisms function in relation to the immunosuppressant drugs, FK506 and rapamycin. Differences that could be used to design insect-specific pesticides. (1) Molecular phylogenetic analysis of FKBP family proteins revealed that the eight known Drosophila FKBPs share homology with the human FKBP12. This indicates a close evolutionary relationship, and possible origination from a common ancestor. (2) The known FKBPs contain FK domains, that is, a prolyl cis/trans isomerase (PPIase) domain that mediates immune suppression through inhibition of calcineurin. The dFKBP59, CG4735/Shutdown, CG1847, and CG5482 have a Tetratricopeptide receptor domain at the C-terminus, which regulates transcription and protein transportation. (3) FKBP51 and FKBP52 (dFKBP59), along with Cyclophilin 40 and protein phosphatase 5, function as Hsp90 immunophilin co-chaperones within steroid receptor-Hsp90 heterocomplexes. These immunophilins are potential drug targets in pathways associated with normal physiology and may be used to treat a variety of steroid-based diseases by targeting exocytic/endocytic cycling and vesicular trafficking. (4) By associating with presinilin, a critical component of the Notch signaling pathway, FKBP14 is a downstream effector of Notch activation at the membrane. Meanwhile, Shutdown associates with transposons in the PIWI-interacting RNA pathway, playing a crucial role in both germ cells and ovarian somas. Mutations in or silencing of dFKBPs lead to early embryonic lethality in Drosophila. Therefore, further understanding the mechanisms of FK506 and rapamycin binding to immunophilin FKBPs in endocrine, cardiovascular, and neurological function in both mammals and Drosophila would provide prospects in generating unique, insect specific therapeutics targeting the above cellular signaling pathways. CONCLUSION: This review will evaluate the functional roles of FKBP family proteins, and systematically summarize the similarities and differences between FKBP proteins in Drosophila and Mammals. Specific therapeutics targeting cellular signaling pathways will also be discussed.


Asunto(s)
Drosophila melanogaster/metabolismo , Mamíferos/metabolismo , Proteínas de Unión a Tacrolimus/química , Proteínas de Unión a Tacrolimus/metabolismo , Secuencia de Aminoácidos , Animales , Evolución Molecular , Humanos , Insecticidas/toxicidad , Filogenia
17.
J Org Chem ; 83(9): 5027-5034, 2018 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-29649365

RESUMEN

A catalytic asymmetric α-arylation of aldehydes using 2-indolylmethanols as arylation reagents has been established. This reaction was enabled by a cooperative catalytic system consisting of a gold complex, a Brønsted acid, and a chiral amine, which have a synergistic effect in the reaction process. By using this strategy, a series of α-arylation products of aldehydes were generated in overall acceptable yields and good enantioselectivities (up to 69%, 91:9 er). The control experiments demonstrated that the addition of PPh3AuCl as a gold complex was helpful to improve the yield, and trifluoroacetic acid as a Brønsted acid played a crucial role in the reaction by promoting the generation of carbocation and chiral enamine intermediates, which are two key intermediates of the asymmetric α-arylation reaction. In addition, the enantioselectivity of the reaction was mainly controlled by the chiral amine catalyst via forming a chiral enamine intermediate. This reaction has not only provided a useful protocol for catalytic asymmetric α-arylation of aldehydes but also enriched the research contents of 2-indolylmethanol-involved reactions and asymmetric cooperative catalysis.

18.
Org Biomol Chem ; 16(9): 1536-1542, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29431794

RESUMEN

A Brønsted acid-catalyzed direct C3-arylation of 2-indolylmethanols with tryptamines and tryptophols has been established, leading to a series of potentially bioactive 2,3'-biindole derivatives with a broad substrate scope and generally good yields (38 examples, up to 96% yield). In this process, the reactivity of the C3-position of 2-indolylmethanol is switched from nucleophilic to electrophilic, which can serve as an umpolung strategy in indole chemistry. This protocol not only provides a new strategy for accessing structurally diversified 2,3'-biindolyl frameworks, but also satisfies the requirement of green chemistry.

19.
J Org Chem ; 82(19): 10226-10233, 2017 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-28920688

RESUMEN

The catalytic asymmetric [3 + 2] cycloaddition of 2-indolylmethanols to p-hydroxystyrenes was established in the presence of a chiral phosphoramide, and this reaction provided chiral cyclopenta[b]indole scaffolds in generally high yields and with good enantioselectivities (up to 98% yield, 99:1 er). The control experiments demonstrated that the dual hydrogen-bonding activation mode of the chiral catalyst toward the two substrates played an important role in the reaction. In addition, the large-scale reaction indicated that this catalytic asymmetric [3 + 2] cycloaddition could be scaled up for the synthesis of chiral cyclopenta[b]indole derivatives.

20.
J Pathol ; 238(1): 31-41, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26331372

RESUMEN

Prostate cancer often manifests as morphologically distinct tumour foci and is frequently found adjacent to presumed precursor lesions such as high-grade prostatic intraepithelial neoplasia (HGPIN). While there is some evidence to suggest that these lesions can be related and exist on a pathological and morphological continuum, the precise clonal and temporal relationships between precursor lesions and invasive cancers within individual tumours remain undefined. Here, we used molecular genetic, cytogenetic, and histological analyses to delineate clonal, temporal, and spatial relationships between HGPIN and cancer lesions with distinct morphological and molecular features. First, while confirming the previous finding that a substantial fraction of HGPIN lesions associated with ERG-positive cancers share rearrangements and overexpression of ERG, we found that a significant subset of such HGPIN glands exhibit only partial positivity for ERG. This suggests that such ERG-positive HGPIN cells either rapidly invade to form adenocarcinoma or represent cancer cells that have partially invaded the ductal and acinar space in a retrograde manner. To clarify these possibilities, we used ERG expression status and TMPRSS2-ERG genomic breakpoints as markers of clonality, and PTEN deletion status to track temporal evolution of clonally related lesions. We confirmed that morphologically distinct HGPIN and nearby invasive cancer lesions are clonally related. Further, we found that a significant fraction of ERG-positive, PTEN-negative HGPIN and intraductal carcinoma (IDC-P) lesions are most likely clonally derived from adjacent PTEN-negative adenocarcinomas, indicating that such PTEN-negative HGPIN and IDC-P lesions arise from, rather than give rise to, the nearby invasive adenocarcinoma. These data suggest that invasive adenocarcinoma can morphologically mimic HGPIN through retrograde colonization of benign glands with cancer cells. Similar clonal relationships were also seen for intraductal carcinoma adjacent to invasive adenocarcinoma. These findings represent a potentially undervalued indicator of pre-existing invasive prostate cancer and have significant implications for prostate cancer diagnosis and risk stratification.


Asunto(s)
Adenocarcinoma/patología , Carcinoma Intraductal no Infiltrante/patología , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/patología , Adenocarcinoma/genética , Carcinoma Intraductal no Infiltrante/genética , Línea Celular Tumoral , Diagnóstico Diferencial , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Masculino , Invasividad Neoplásica , Proteínas de Fusión Oncogénica/genética , Fosfohidrolasa PTEN/genética , Neoplasia Intraepitelial Prostática/genética , Neoplasias de la Próstata/genética , Transactivadores/genética , Regulador Transcripcional ERG
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