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1.
Pharmacol Rev ; 75(3): 532-553, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36627210

RESUMEN

The development of cutting-edge techniques to study specific brain regions and neural circuits that regulate sleep-wake brain states and general anesthesia (GA), has increased our understanding of these states that exhibit similar neurophysiologic traits. This review summarizes current knowledge focusing on cell subtypes and neural circuits that control wakefulness, rapid eye movement (REM) sleep, non-REM sleep, and GA. We also review novel insights into their interactions and raise unresolved questions and challenges in this field. Comparisons of the overlapping neural substrates of sleep-wake and GA regulation will help us to understand sleep-wake transitions and how anesthetics cause reversible loss of consciousness. SIGNIFICANCE STATEMENT: General anesthesia (GA), sharing numerous neurophysiologic traits with the process of natural sleep, is administered to millions of surgical patients annually. In the past decade, studies exploring the neural mechanisms underlying sleep-wake and GA have advanced our understanding of their interactions and how anesthetics cause reversible loss of consciousness. Pharmacotherapies targeting the neural substrates associated with sleep-wake and GA regulations have significance for clinical practice in GA and sleep medicine.


Asunto(s)
Sueño REM , Sueño , Humanos , Sueño REM/fisiología , Anestesia General/efectos adversos , Encéfalo/fisiología , Inconsciencia
2.
J Virol ; 98(5): e0195923, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38634598

RESUMEN

The role of Culex mosquitoes in the transmission of Japanese encephalitis virus (JEV) is crucial, yet the mechanisms of JEV infection in these vectors remain unclear. Previous research has indicated that various host factors participate in JEV infection. Herein, we present evidence that mosquito sialic acids enhance JEV infection both in vivo and in vitro. By treating mosquitoes and C6/36 cells with neuraminidase or lectin, the function of sialic acids is effectively blocked, resulting in significant inhibition of JEV infection. Furthermore, knockdown of the sialic acid biosynthesis genes in Culex mosquitoes also leads to a reduction in JEV infection. Moreover, our research revealed that sialic acids play a role in the attachment of JEV to mosquito cells, but not in its internalization. To further explore the mechanisms underlying the promotion of JEV attachment by sialic acids, we conducted immunoprecipitation experiments to confirm the direct binding of sialic acids to the last α-helix in JEV envelope protein domain III. Overall, our study contributes to a molecular comprehension of the interaction between mosquitoes and JEV and offers potential strategies for preventing the dissemination of flavivirus in natural environments.IMPORTANCEIn this study, we aimed to investigate the impact of glycoconjugate sialic acids on mosquito infection with Japanese encephalitis virus (JEV). Our findings demonstrate that sialic acids play a crucial role in enhancing JEV infection by facilitating the attachment of the virus to the cell membrane. Furthermore, our investigation revealed that sialic acids directly bind to the final α-helix in the JEV envelope protein domain III, thereby accelerating virus adsorption. Collectively, our results highlight the significance of mosquito sialic acids in JEV infection within vectors, contributing to a better understanding of the interaction between mosquitoes and JEV.


Asunto(s)
Culex , Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Ácidos Siálicos , Acoplamiento Viral , Animales , Ratones , Línea Celular , Culex/virología , Culex/metabolismo , Virus de la Encefalitis Japonesa (Especie)/fisiología , Virus de la Encefalitis Japonesa (Especie)/metabolismo , Encefalitis Japonesa/virología , Encefalitis Japonesa/metabolismo , Mosquitos Vectores/virología , Neuraminidasa/metabolismo , Neuraminidasa/genética , Ácidos Siálicos/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Proteínas del Envoltorio Viral/genética , Internalización del Virus
3.
Exp Dermatol ; 33(3): e15059, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38532578

RESUMEN

Psoriasis is a common chronic inflammatory skin disease with a complex pathogenesis involving immune system dysregulation and inflammation. Previous studies have indicated that metabolic abnormalities are closely related to the development and occurrence of psoriasis. However, the specific involvement of amino acid metabolism in the pathogenesis of psoriasis remains unclear. In this study, we conducted a comprehensive analysis of amino acid metabolism pathway changes in psoriasis patients using transcriptome data, genome-wide association studies (GWASs) data, and single-cell data. Our findings revealed 11 significant alterations in amino acid metabolism pathways within psoriatic lesions, with notable restorative changes observed after biological therapy. Branched-chain amino acids, tyrosine and arginine metabolism have a causal relationship with the occurrence of psoriasis and may play a crucial role by promoting the proliferation and differentiation of the keratinocytes or immune-related pathways. Activation of phenylalanine, tyrosine and tryptophan biosynthesis suggests a favourable prognosis of psoriasis after treatment. Additionally, we identified the abnormal metabolic pathways in specific cell types and key gene sets that contribute to amino acid metabolic disorders in psoriasis. Overall, our study enhances understanding of the role of metabolism in the pathogenesis of psoriasis and provides potential targets for developing new therapeutic strategies for the disease.


Asunto(s)
Aminoácidos , Psoriasis , Humanos , Estudio de Asociación del Genoma Completo , Psoriasis/tratamiento farmacológico , Queratinocitos/metabolismo , Redes y Vías Metabólicas , Tirosina/genética
4.
Chemistry ; 30(15): e202304134, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38205620

RESUMEN

A 14-electron ternary anionic CBe2 H5 - cluster containing a planar tetracoordinate carbon (ptC) atom is designed herein. Remarkably, it can be stabilized by only two beryllium atoms with both π-acceptor/σ-donor properties and two hydrogen atoms, which means that the conversion from planar methane (transition state) to ptC species (global minimum) requires the substitution of only two hydrogen atoms. Moreover, two ligand H atoms exhibit alternate rotation, giving rise to interesting dynamic fluxionality in this cluster. The electronic structure analysis reveals the flexible bonding positions of ligand H atoms due to C-H localized bonds, highlighting the rotational fluxionality in the cluster, and two CBe2 3c-2e delocalized bonds endow its rare 2σ/2π double aromaticity. Unprecedentedly, the fluxional process exhibits a conversion in the type of bonding (σ bond↔π bond), which is an uncommon fluxional mechanism. The cluster can be seen as an attempt to apply planar hypercoordinate carbon species to molecular motors.

5.
Chemistry ; : e202402132, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973769

RESUMEN

The design of boron-based molecular rotors stems from boron-carbon binary clusters containing multiple planar hypercoordinate carbons (phCs, such as C2B8). However, the design of boron-coordinated phCs is challenging due to boron's tendency to occupy hypercoordinate centers more than carbon. Although this challenge has been addressed, the designed clusters of interest have not exhibited dynamic fluxionality similar to that of the initial C2B8. To address this issue, we report a σ/π doubly aromatic CB2H5+ cluster, the first global minimum containing a boron-coordinated planar tetracoordinate carbon atom with dynamic fluxionality. Dynamics simulations show that two ligand H atoms exhibit alternate rotation, resulting in an intriguing dynamic fluxionality in this cluster. Electronic structure analysis reveals the flexible bonding positions of the ligand H atoms because they do not participate in π delocalized bonding nor bond to any other non-carbon atom, highlighting this rotational fluxionality. Unprecedentedly, the fluxional process involves not only the usual conversion of the number of bonding atoms, but also the type of bonding (3c π bonds ↔ 4c σ bonds), which is an uncommon fluxional mechanism. The cluster represents an effort to apply phC species to molecular machines.

6.
J Org Chem ; 87(24): 16851-16859, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36416373

RESUMEN

We report herein the Pd-catalyzed selective ring-opening reaction of cyclopropenones with vinyl epoxides. By using a commercially available Pd2(dba)3·CHCl3-BINAP catalyst, a wide range of conjugated alkadienyl carboxylates could be accessed in good yield and excellent regioselectivity. The new application of zwitterionic π-allyl palladium intermediates has been demonstrated in organic synthesis.

7.
Phys Chem Chem Phys ; 24(46): 28548-28553, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36411992

RESUMEN

Computational evidence is reported for the largest planar molecular wheel of the Y©B8C4 cluster, featuring an yttrium atom enclosed by a highly symmetric B8C4 ring. The B8C4 ring is viable in the -(BCB)4- form with double 9π/10σ aromaticity. The centered yttrium atom is dodeca-coordinated with the peripheral B8C4 ring, which sets a record coordination number for a planar structure in chemistry heretofore.

8.
J Cell Physiol ; 236(6): 4445-4454, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33184860

RESUMEN

Morphine, a mu-opioid receptor (MOR) agonist, has been extensively used to treat advanced cancer pain. In particular, in patients with cancer metastasis, both morphine and anticancer drugs are given simultaneously. However, evidence showed that morphine might be a risk factor in promoting the tumor's malignant potential. In this study, we report that treatment with morphine could activate MOR and lead to the promotion of proliferation, migration, and invasion in HCT116 and DLD1 colorectal cancer (CRC) cells with time-concentration dependence. Moreover, morphine can also contribute to cetuximab's drug resistance, a targeted drug widely used to treat advanced CRC by inducing the activation of epidermal growth factor receptor (EGFR). The cell phenotype includes proliferation, migration, invasion, and drug resistance, which may be reversed by MOR knockdown or adding nalmefene, the MOR receptor antagonist. Receptor tyrosine kinase array analysis revealed that morphine selectively induced the transactivation of EGFR. EGFR transactivation resulted in the activation of ERK1/2 and AKT. In conclusion, morphine induces the transactivation of EGFR via MOR. It activates the downstream signal pathway AKT-MTOR and RAS-MAPK, increases proliferation, migration, and invasion, and promotes resistance to EGFR inhibitors in a CRC cell line. Furthermore, we verified that EGFR inhibition by cetuximab strongly reversed the protumoral effects of morphine in vitro and in vivo. Collectively, we provide evidence that morphine-EGFR signaling might be a promising therapeutic target for CRC patients, especially for cetuximab-resistant CRC patients.


Asunto(s)
Antineoplásicos Inmunológicos/farmacología , Cetuximab/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos , Morfina/toxicidad , Receptores Opioides mu/agonistas , Animales , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células HCT116 , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas ras/metabolismo
9.
Chemistry ; 27(3): 944-948, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33044750

RESUMEN

This work reports a green method for the synthesis of aryl selenocyanates via a three-component reaction of arylboronic acids, Se powder, and trimethylsilyl cyanide (TMSCN) under metal-free and additive-free conditions. Remarkably, TMSCN acts as not only the substrate, but also the catalyst. Various selenaheterocycles can be also accessed with a catalytic amount of TMSCN.

10.
J Org Chem ; 86(23): 17294-17306, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34784197

RESUMEN

A facile method is disclosed for the synthesis of α-thio/selenocyanato ketones through regioselective C-H thio/selenocyanation of ketones. The advantages include the use of easily available starting materials, high efficiency, simple operation, and easy scale-up. Control experiments provide evidence that the reaction proceeded via a radical way, while kinetic isotope effect experiments reveal that the cleavage of the C-H bond serves as the rate-limiting step.

11.
Org Biomol Chem ; 19(38): 8250-8253, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34518849

RESUMEN

An atom economical protocol for the construction of 9-(diorganomethylidene)fluorenes through palladium-catalyzed coupling reactions of 2-iodobiphenyls with alkenyl bromides has been reported. The reaction proceeds through the C-H activation/oxidative addition/reduction elimination/intramolecular Heck coupling reaction to afford a series of 9-(diorganomethylidene)fluorenes with good yields. Control experiments demonstrate that a five-membered palladacycle acts as a key intermediate and ß-H elimination serves as the rate-limiting step.

12.
Org Biomol Chem ; 18(30): 5822-5825, 2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32691814

RESUMEN

Ag2O-promoted ring-opening reactions of cyclopropenones with oximes is disclosed in this work, providing a direct route to 1,3-oxazinones. This method highlights a new reactivity of cyclopropenones which undergo 1,4-addition with oximes followed by ß-carbon elimination to in situ generate a α-carbonyl ketene intermediate.

13.
Phys Chem Chem Phys ; 22(36): 20362-20367, 2020 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-32901630

RESUMEN

The typical electron-deficiency of the boron element renders fascinating architectures and chemical bonding to boron-based nanoclusters. We theoretically predict two di-Ca-doped boron clusters, B6Ca2 (D2h, 1Ag) and B8Ca2 (D8h, 1A1g), and both adopt interesting inverse sandwich geometries, showing an elongated D2h B6 or perfectly planar D8h B8 ring being sandwiched by two Ca atoms only, respectively. Natural atomic charge analyses indicate that the Ca atoms donate nearly all the 4s electrons to the B6 (or B8) ring, forming [Ca]2+[B6]4-[Ca]2+ and [Ca]2+[B8]4-[Ca]2+ charge transfer complexes. The interaction between the two Ca atoms and the boron rings is governed by robust electrostatics albeit by weaker B-Ca covalent interaction. Chemical bonding analyses show that B6Ca2 has 4σ and 6π delocalized electrons on the elongated B6 ring, leading to a conflicting aromatic system. B8Ca2, possessing 6σ and 6π delocalized electrons on the B8 ring, is doubly aromatic. Additionally, the B6Ca2 and B8Ca2 clusters show noticeable structural and electronic transmutation relative to their equivalent electronic B6Be2 and B8Mg2 clusters, respectively. The intrinsic reasons behind the transmutations are elucidated via in-depth bonding analyses.

14.
Phys Chem Chem Phys ; 22(35): 20043-20049, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32936150

RESUMEN

Computational evidence is reported on a boron-based ternary Rb6Be2B6 cluster as the "Big Mac" sandwich on a subnanoscale with thickness of 0.58 nm. The core hexagonal B6 ring, occurring in the naked form due to double 6π/6σ aromaticity, is capped by two tetrahedral BeRb3 ligands. Such a B6 motif is scarce in boron clusters. The sandwich cluster has four-fold 2σ/6π/6σ/2σ aromaticity and its tetrahedral BeRb3 ligand is the simplest case of three-dimensional aromaticity (or spherical aromaticity). The sandwich can be formulated as a charge-transfer complex, [Rb3Be]3+[B6]6-[BeRb3]3+, whose components are held together by robust electrostatics, facilitating dual-mode dynamic fluxionality.

15.
BMC Anesthesiol ; 20(1): 204, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32799814

RESUMEN

BACKGROUND: Postoperative pain in ambulatory surgery is a multifactorial issue affecting patient satisfaction, time of discharge, and rehospitalization. This study evaluated the efficacy and safety of nalbuphine for the treatment of postoperative pain after ambulatory surgery, relative to tramadol. METHODS: This multi-center, randomized, double blind, and controlled study was conducted at 10 centers. In accordance with the inclusion criteria, 492 ambulatory surgery patients were recruited. These patients had moderate to severe pain after ambulatory surgery, with a visual analogue scale (VAS) score > 3 cm. They were randomly divided into an experimental (n = 248) or control (n = 244) group and treated for analgesia with 0.2 mg/kg of nalbuphine or 2 mg/kg of tramadol, respectively. VAS scores, adverse events, and vital signs of the patients were recorded before administration (baseline; T1); and 30 min (T2), 2 h (T3), 4 h (T4), and 6 h (T5) after administration of analgesia. A decrease in pain intensity of more than 25% compared with the baseline was used as an indicator of analgesic efficacy. The experimental and control groups were compared with regard to this indicator of efficacy at each timepoint. RESULTS: The VAS scores of the experimental and control groups were statistically comparable at timepoints T1-T4. At T5, the VAS scores of the experimental group were significantly lower than that of the control. The pain intensity was significantly higher in the experimental group compared with the control at T2 and T3. Adverse events and vital signs were similar for the two groups at each timepoint. CONCLUSIONS: Nalbuphine can provide effective and safe pain relief in patients after ambulatory surgery. TRIAL REGISTRATION: The registration number is ChiCTR-IOR-16010032 , the date of registration was 2016-11-28.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/métodos , Analgésicos Opioides/administración & dosificación , Nalbufina/administración & dosificación , Manejo del Dolor/métodos , Dolor Postoperatorio/tratamiento farmacológico , Tramadol/administración & dosificación , Adulto , Procedimientos Quirúrgicos Ambulatorios/efectos adversos , Analgésicos Opioides/efectos adversos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nalbufina/efectos adversos , Dolor Postoperatorio/diagnóstico , Náusea y Vómito Posoperatorios/inducido químicamente , Náusea y Vómito Posoperatorios/diagnóstico , Estudios Prospectivos , Tramadol/efectos adversos
16.
Microb Pathog ; 134: 103596, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31212036

RESUMEN

To establish infection in the host, pathogens have evolved sophisticated systems to cope with environmental conditions and to protect cells against host immunity. TolC is the outer membrane channel component of type 1 secretion systems and multidrug efflux pumps that plays critical roles during the infection process in many pathogens. However, little is known about the exact roles of TolC1 in the pathogenicity of A. pleuropneumoniae, an etiological agent of the porcine contagious pleuropneumoniae that causes severe respiratory disease. In this study, deletion of tolC1 causes apparent ultrastructural defects in A. pleuropneumoniae cell examined by transmission electron microscopy. The tolC1 mutant is hypersensitivity to oxidative, osmotic and acid challenges by in vitro stress assays. Analysis on secreted proteins shows that the excretion of ApxIIA and an ApxIVA-like protein, ApxIVA-S, is abolished in the absence of TolC1. This result confirms the essential role of TolC1 in the secretion of Apx toxins and this is the first identification of an ApxIVA-like protein in in vitro culture of A. pleuropneumoniae. Besides, disruption of TolC1 leads to a significant attenuation of virulence in mice by an intraperitoneal route of A. pleuropneumoniae. The basis for the attenuation is further investigated using a mouse intranasal infection model, which reveals an impaired ability to colonize and induce lesions in the lungs for the loss of TolC1 of A. pleuropneumoniae. In conclusion, our findings demonstrate significant roles of TolC1 in facilitating bacterial survival in hostile conditions, maximum colonization as well as pathogenicity during the infection of A. pleuropneumoniae.


Asunto(s)
Infecciones por Actinobacillus/microbiología , Actinobacillus pleuropneumoniae/fisiología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Factores de Virulencia/metabolismo , Infecciones por Actinobacillus/patología , Actinobacillus pleuropneumoniae/citología , Actinobacillus pleuropneumoniae/patogenicidad , Animales , Proteínas de la Membrana Bacteriana Externa/clasificación , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/genética , Modelos Animales de Enfermedad , Eliminación de Gen , Genes MDR , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Interacciones Huésped-Patógeno/fisiología , Pulmón/microbiología , Pulmón/patología , Ratones , Presión Osmótica , Estrés Oxidativo , Proteoma/análisis , Proteoma/aislamiento & purificación , Proteínas Recombinantes , Estrés Fisiológico , Transcriptoma , Sistemas de Secreción Tipo I/química , Sistemas de Secreción Tipo I/genética , Sistemas de Secreción Tipo I/metabolismo , Virulencia , Factores de Virulencia/genética
17.
Acta Pharmacol Sin ; 40(10): 1303-1313, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31235816

RESUMEN

Metalloproteinase 9 (MMP-9) is able to degrade collagen IV, an important component of blood-brain barrier (BBB). Expression of MMPs, especially MMP-9, correlates with BBB disruption during central nervous system inflammation. Propofol has been reported to have anti-inflammation effects. In this study, we investigated the effects of propofol on TNF-α-induced MMP-9 expression in human cerebral microvascular endothelial cells (hCMEC/D3 cells) and explored the underlying mechanisms. The hCMEC/D3 cells were treated with propofol (25 µM), followed by TNF-α (25 ng/mL). We showed that TNF-α treatment markedly increased MMP-9 expression and decreased collagen IV expression in hCMEC/D3 cells, which was blocked by pretreatment with propofol. TNF-α-induced downregulation of collagen IV was also reversed by MMP-9 knockdown with siRNA. We revealed that TNF-α upregulated MMP-9 expression in hCMEC/D3 cells through activation of Ca2+/CAMK II/ERK/NF-κB signaling pathway; co-treatment with inhibitors of CaMK II (KN93), ERK (LY3214996), NF-κB (PDTC) or Ca2+chelator (BAPTA-AM) abrogated the effect of TNF-α on MMP-9 expression. We further established an in vitro BBB model by co-culturing of hCMEC/D3 cells and human astrocytes for 6 days and measuring trans-endothelial electrical resistance (TEER) to reflect the BBB permeability. TNF-α treatment markedly decreased TEER value, which was attenuated by pretreatment with propofol (25 µM) or MMP-9 knockdown with siRNA. In conclusion, propofol inhibits TNF-α-induced MMP-9 expression in hCMEC/D3 cells via repressing the Ca2+/CAMKII/ERK/NF-κB signaling pathway. TNF-α-impaired BBB integrity could be reversed by propofol, and propofol attenuates the inhibitory effect of TNF-α on collagen IV.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/genética , Microvasos/efectos de los fármacos , Propofol/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/antagonistas & inhibidores , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/metabolismo , Microvasos/metabolismo , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/metabolismo
18.
Int J Mol Sci ; 20(22)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739611

RESUMEN

The Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus prevalent in east and southeast Asia, the Western Pacific, and northern Australia. Since viruses are obligatory intracellular pathogens, the dynamic processes of viral entry, replication, and assembly are dependent on numerous host-pathogen interactions. Efforts to identify JEV-interacting host factors are ongoing because their identification and characterization remain incomplete. Three enzymatic activities of flavivirus non-structural protein 3 (NS3), including serine protease, RNA helicase, and triphosphatase, play major roles in the flaviviruses lifecycle. To identify cellular factors that interact with NS3, we screened a human brain cDNA library using a yeast two-hybrid assay, and identified eight proteins that putatively interact with NS3: COPS5, FBLN5, PPP2CB, CRBN, DNAJB6, UBE2N, ZNF350, and GPR137B. We demonstrated that the DnaJ heat shock protein family (Hsp40) member B6 (DNAJB6) colocalizes and interacts with NS3, and has a negative regulatory function in JEV replication. We also show that loss of DNAJB6 function results in significantly increased viral replication, but does not affect viral binding or internalization. Moreover, the time-course of DNAJB6 disruption during JEV infection varies in a viral load-dependent manner, suggesting that JEV targets this host chaperone protein for viral benefit. Deciphering the modes of NS3-interacting host proteins functions in virion production will shed light on JEV pathogenic mechanisms and may also reveal new avenues for antiviral therapeutics.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/fisiología , Encefalitis Japonesa/metabolismo , Encefalitis Japonesa/virología , Proteínas del Choque Térmico HSP40/metabolismo , Interacciones Huésped-Patógeno , Chaperonas Moleculares/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Línea Celular , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Interacciones Huésped-Patógeno/genética , Humanos , Unión Proteica , Mapeo de Interacción de Proteínas , Transporte de Proteínas , ARN Helicasas/metabolismo , Serina Endopeptidasas/metabolismo , Técnicas del Sistema de Dos Híbridos , Internalización del Virus
19.
Phys Chem Chem Phys ; 18(17): 11610-5, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-26738471

RESUMEN

Based on extensive global-minimum searches and first-principles electronic structure calculations, we present the viability of an endohedral metalloborospherene Cs Ca@B38 () which contains a Cs B38(2-) () dianion composed of interwoven boron double chains with a σ + π double delocalization bonding pattern, extending the Bn(q) (q = n - 40) borospherene family from n = 39-42 to n = 38. Transition metal endohedral complexes Cs M@B38 (M = Sc, Y, Ti) (, , ) based on Cs B38(2-) () are also predicted.

20.
Phys Chem Chem Phys ; 18(42): 29147-29155, 2016 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-27730232

RESUMEN

Size-selected boron clusters have been found to be predominantly planar or quasi-planar (2D) in the small size regime with the appearance of three-dimensional (3D) borospherene cages of larger sizes. A seashell-like B28- cluster was previously shown to be the smallest borospherene, which competes with a quasi-planar isomer for the global minimum. Here we report a study on the structures and bonding of the B29- and B29 clusters using photoelectron spectroscopy (PES) and first-principles calculations and demonstrate the continued competition between the 2D and borospherene structures. The PES spectrum of B29- displays a complex pattern with evidence of low-lying isomers. Global-minimum searches and extensive theoretical calculations revealed a complicated potential energy surface for B29- with five low-lying isomers, among which the lowest three were shown to contribute to the experimental spectrum. A 3D seashell-like Cs (2, 1A') isomer, featuring two heptagons on the waist and one octagon at the bottom, is the global minimum for B29-, followed by a 2D C1 (3, 1A) isomer with a hexagonal hole and a stingray-shaped 2D Cs (1, 1A') isomer with a pentagonal hole. However, by taking into account the entropic effects, the stingray-shaped isomer 1 was shown to be the lowest in energy at room temperature and was found to dominate the PES spectrum. Isomers 2 and 3, which have lower electron binding energies, were also found to be present in the experiment. Chemical bonding analyses showed that isomer 1 is an all-boron analogue of benzo[ghi]fluoranthene (C18H10), whereas the borospherene isomer 2 possesses 18π electrons, conforming to the 2(N + 1)2 electron counting rule for spherical aromaticity. For the B29 neutral cluster, the seashell-like borospherene isomer is the global minimum, significantly lower in energy than the stingray-shaped quasi-planar structure.

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