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Cancer vaccines have been developed as a promising way to boost cancer immunity. However, their clinical potency is often limited due to the imprecise delivery of tumor antigens. To overcome this problem, we conjugated an endogenous Toll-like receptor (TLR)2/6 ligand, UNE-C1, to human papilloma virus type 16 (HPV-16)-derived peptide antigen, E7, and found that the UNE-C1-conjugated cancer vaccine (UCV) showed significantly enhanced antitumor activity in vivo compared with the noncovalent combination of UNE-C1 and E7. The combination of UCV with PD-1 blockades further augmented its therapeutic efficacy. Specifically, the conjugation of UNE-C1 to E7 enhanced its retention in inguinal draining lymph nodes, the specific delivery to dendritic cells and E7 antigen-specific T cell responses, and antitumor efficacy in vivo compared with the noncovalent combination of the two peptides. These findings suggest the potential of UNE-C1 derived from human cysteinyl-tRNA synthetase 1 as a unique vehicle for the specific delivery of cancer antigens to antigen-presenting cells via TLR2/6 for the improvement of cancer vaccines.
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Tetrodotoxin (TTX) poisoning through the consumption of contaminated fish leads to lethal symptoms, including severe hypotension. This TTX-induced hypotension is likely due to the downfall of peripheral arterial resistance through direct or indirect effects on adrenergic signaling. TTX is a high-affinity blocker of voltage-gated Na+ (NaV) channels. In arteries, NaV channels are expressed in sympathetic nerve endings, both in the intima and media. In this present work, we aimed to decipher the role of NaV channels in vascular tone using TTX. We first characterized the expression of NaV channels in the aorta, a model of conduction arteries, and in mesenteric arteries (MA), a model of resistance arteries, in C57Bl/6J mice, by Western blot, immunochemistry, and absolute RT-qPCR. Our data showed that these channels are expressed in both endothelium and media of aorta and MA, in which scn2a and scn1b were the most abundant transcripts, suggesting that murine vascular NaV channels consist of NaV1.2 channel subtype with NaVß1 auxiliary subunit. Using myography, we showed that TTX (1 µM) induced complete vasorelaxation in MA in the presence of veratridine and cocktails of antagonists (prazosin and atropine with or without suramin) that suppressed the effects of neurotransmitter release. In addition, TTX (1 µM) strongly potentiated the flow-mediated dilation response of isolated MA. Altogether, our data showed that TTX blocks NaV channels in resistance arteries and consecutively decreases vascular tone. This could explain the drop in total peripheral resistance observed during mammal tetrodotoxications.
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Aorta , Artérias Mesentéricas , Camundongos , Animais , Tetrodotoxina/farmacologia , Mamíferos , Subunidade beta-1 do Canal de Sódio Disparado por VoltagemRESUMO
Thanks to the crosstalk between Na+ and Ca2+ channels, Na+ and Ca2+ homeostasis interplay in so-called excitable cells enables the generation of action potential in response to electrical stimulation. Here, we investigated the impact of persistent activation of voltage-gated Na+ (NaV) channels by neurotoxins, such as veratridine (VTD), on intracellular Ca2+ concentration ([Ca2+]i) in a model of excitable cells, the rat pituitary GH3b6 cells, in order to identify the molecular actors involved in Na+-Ca2+ homeostasis crosstalk. By combining RT-qPCR, immunoblotting, immunocytochemistry, and patch-clamp techniques, we showed that GH3b6 cells predominantly express the NaV1.3 channel subtype, which likely endorses their voltage-activated Na+ currents. Notably, these Na+ currents were blocked by ICA-121431 and activated by the ß-scorpion toxin Tf2, two selective NaV1.3 channel ligands. Using Fura-2, we showed that VTD induced a [Ca2+]i increase. This effect was suppressed by the selective NaV channel blocker tetrodotoxin, as well by the selective L-type CaV channel (LTCC) blocker nifedipine. We also evidenced that crobenetine, a NaV channel blocker, abolished VTD-induced [Ca2+]i elevation, while it had no effects on LTCC. Altogether, our findings highlight a crosstalk between NaV and LTCC in GH3b6 cells, providing a new insight into the mode of action of neurotoxins.
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Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Canais de Sódio Disparados por Voltagem/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Fenômenos Eletrofisiológicos , Imunofluorescência , Expressão Gênica , Ensaios de Triagem em Larga Escala , Ativação do Canal Iônico/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Neurotoxinas/farmacologia , Técnicas de Patch-Clamp , Ligação Proteica , Isoformas de Proteínas , Ratos , Canais de Sódio Disparados por Voltagem/genéticaRESUMO
BACKGROUND: Phosphorylation of NF-kappaB inhibitor alpha (IκBα) is key to regulation of NF-κB transcription factor activity in the cell. Several sites of IκBα phosphorylation by members of the IκB kinase family have been identified, but phosphorylation of the protein by other kinases remains poorly understood. We investigated a new phosphorylation site on IκBα and identified its biological function in breast cancer cells. METHODS: Previously, we observed that aurora kinase (AURK) binds IκBα in the cell. To identify the domains of IκBα essential for phosphorylation by AURK, we performed kinase assays with a series of IκBα truncation mutants. AURK significantly promoted activation of IκBα at serine 32 but not serine 36; by contrast, IκB kinase (IKK) family proteins activated both of these residues. We also confirmed phosphorylation of IκBα by matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) and nano-liquid chromatography hybrid quadrupole orbitrap mass spectrometer (nanoLC-MS/MS; Q-Exactive). RESULTS: We identified two novel sites of serine phosphorylation, S63 and S262. Alanine substitution of S63 and S262 (S63A and S262A) of IκBα inhibited proliferation and suppressed p65 transcription activity. In addition, S63A and/or S262A of IκBα regulated apoptotic and necroptotic effects in breast cancer cells. CONCLUSIONS: Phosphorylation of IκBα by AURK at novel sites is related to the apoptosis and necroptosis pathways in breast cancer cells.
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Aurora Quinase C/metabolismo , Neoplasias da Mama/patologia , Inibidor de NF-kappaB alfa/metabolismo , Necroptose , Sítios de Ligação/genética , Feminino , Humanos , Células MCF-7 , Mutagênese Sítio-Dirigida , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/isolamento & purificação , NF-kappa B/metabolismo , Fosforilação , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
Neonicotinoid insecticides are nicotine-derived molecules which exert acute neurotoxic effects over the insect central nervous system by activating nicotinic acetylcholine receptors (nAChRs). However, these receptors are also present in the mammalian central and peripheral nervous system, where the effects of neonicotinoids are faintly known. In mammals, cholinergic synapses are crucial for the control of vascular tone, blood pressure and skeletal muscle contraction. We therefore hypothesized that neonicotinoids could affect cholinergic networks in mammals and sought to highlight functional consequences of acute intoxication in rats with sub-lethal concentrations of the highly used acetamiprid (ACE) and clothianidin (CLO). In this view, we characterized their electrophysiological effects on rat α3ß4 nAChRs, knowing that it is predominantly expressed in ganglia of the vegetative nervous system and the adrenal medulla, which initiates catecholamine secretion. Both molecules exhibited a weak agonist effect on α3ß4 receptors. Accordingly, their influence on epinephrine secretion from rat adrenal glands was also weak at 100 µM, but it was stronger at 500 µM. Challenging ACE or CLO together with nicotine (NIC) ended up with paradoxical effects on secretion. In addition, we measured the rat arterial blood pressure (ABP) in vivo by arterial catheterization. As expected, NIC induced a significant increase in ABP. ACE and CLO did not affect the ABP in the same conditions. However, simultaneous exposure of rats to both NIC and ACE/CLO promoted an increase of ABP and induced a biphasic response. Modeling the interaction of ACE or CLO on α3ß4 nAChR is consistent with a binding site located in the agonist pocket of the receptor. We present a transversal experimental approach of mammal intoxication with neonicotinoids at different scales, including in vitro, ex vivo, in vivo and in silico. It paves the way of the acute and chronic toxicity for this class of insecticides on mammalian organisms.
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Epinefrina/metabolismo , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nicotina/toxicidade , Receptores Nicotínicos/metabolismo , Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/metabolismo , Animais , Pressão Arterial/efeitos dos fármacos , Modelos Animais de Doenças , Agonismo Parcial de Drogas , Gânglios/efeitos dos fármacos , Gânglios/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Guanidinas/toxicidade , Masculino , Ratos , Tiazóis/toxicidade , Testes de Toxicidade SubagudaRESUMO
It is highly challenging to develop fast and sensitive fluorescent methods for monitoring organic mercury in purely aqueous solutions as well as live cells. Especially, selective fluorescent detection of methylmercury over inorganic mercury ions has not been reported. We developed a fast and sensitive fluorescent detection method for Hg2+ ions as well as methylmercury using an amino acid-based fluorescent probe (1) and SDS micelles. The fluorescent probe in SDS micelles detected sensitively and selectively Hg2+ ions and methylmercury among 16 metal ions in purely aqueous solution by the enhancement of the red emission at 575 nm, and the detection of methylmercury was completed within 1 min. The probe in SDS micelles with EDTA showed highly sensitive and selective turn on detection for methylmercury over Hg2+. The limit of detection was 9.1 nM for Hg2+ (1.8 ppb, R2 = 0.989) and 206 nM for CH3Hg+ (R2 = 0.997). 1 rapidly penetrated live cells and detected intracellular Hg2+ ions as well as CH3Hg+ by the enhancement of both red emissions and green emissions. Subsequent treatment of EDTA into the cell confirmed the selective detection of methylmercury in the cells. The present work indicated that the fluorescent probe with micelle systems provided a fast, sensitive, and selective detection method for monitoring inorganic mercury as well as methyl mercury.
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Corantes Fluorescentes/química , Compostos de Metilmercúrio/análise , Poluentes Químicos da Água/química , Células A549 , Humanos , Micelas , Conformação Molecular , Imagem Óptica , Soluções , Espectrometria de FluorescênciaRESUMO
Indium has been regarded as one of the most rarely used metal ions; however, the consumption of indium has increased intensively due to its increasing use in electrodes of liquid crystal displays (LCDs). In recent years, warnings have been issued about the toxicity of indium to aquatic ecosystems and humans. Thus, the development of efficient and selective detection methods for In3+ in aquatic environments as well as in live cells is highly required. However, the selective and sensitive detection of In3+ in the presence of trivalent metal ions and other metal ions is highly challenging. In the present study, we synthesized a fluorescent probe (1) for In3+ and Al3+ based on an unnatural peptide receptor and an aggregation-induced emission fluorophore and developed a selective fluorescent detection method for In3+ in aqueous solutions and live cells using the probe and a metal chelating agent. 1 recognized In3+ and Al3+ selectively among 19 metal ions in aqueous solutions depending on pH by the enhancement of the red emission at 600 nm and decrease in the green emission at 530 nm. 1 sensitively detected In3+ and Al3+ by ratiometric response in a wide pH range (3.5-7.4), and the ratiometric response was complete within 20 seconds in an aqueous buffered solution at pH 5.0. Interestingly, the addition of EDTA to the complex of 1 with In3+ or Al3+ did not induce the Al3+-free spectrum but instead induced the In3+-free spectrum; thus, In3+ and Al3+ could be easily differentiated. The detection limit of 1 for In3+ ions was 211 nM (R2 = 0.981) in purely aqueous solutions. The fluorescence ratiometric detection method using 1 could quantify low concentrations of In3+ in ground water and tap water. Fluorescence cell image studies revealed that the probe was cell-permeable, and low concentrations of In3+ inside the cells could be recognized by the enhancement of the red emission at 600 nm. The binding mode study via NMR, IR, and CD spectroscopy revealed how the peptide receptor of 1 interacted with In3+ and resulted in the enhancement of the red emission in an aqueous solution.
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Quelantes/química , Corantes Fluorescentes/química , Índio/análise , Peptídeos/química , Poluentes Químicos da Água/análise , Alumínio/análise , Linhagem Celular Tumoral , Quelantes/síntese química , Água Potável/análise , Corantes Fluorescentes/síntese química , Água Subterrânea/análise , Humanos , Limite de Detecção , Microscopia Confocal , Microscopia de Fluorescência , Peptídeos/síntese química , Espectrometria de FluorescênciaRESUMO
Indium is one of the most widely used scarce metals for manufacturing various electronic devices including notebooks, mobile phones, and PC monitors. Recent studies revealed that indium and its compound could cause several toxicities to human beings and animals. However, there is no report about ratiometric fluorescent detection of In(III) in aqueous solutions. We synthesized a fluorescent probe (1) for In(III) based on a phosphoserine as a receptor with a pyrene fluorophore using solid phase synthesis. 1 showed highly sensitive ratiometric response to In(III) in purely aqueous solutions by increasing excimer emission intensity at 476 nm with a concomitant decrease in monomer emission intensity at 395 nm. 1 showed sensitive ratiometric responses to In(III) over a wide range of pH (2 < pH < 8) and exhibited a highly selective ratiometric response to In(III) among 18 tested metal including Al(III) and Ga(III). Job's plot analysis indicated that 1 preferred to form a 2:1 complex with In(III) and the binding affinity for In(III) was measured to be 2.3 × 1012 M-2 ( R2 = 0.989). 1 showed linear ratiometric responses to nanomolar concentrations (0-750 nM) of In(III) and the detection limit was calculated to be 64 nM ( R2 = 0.992) in aqueous solution. The binding mode study using NMR, IR, and CD spectroscopies revealed that the phosphate and the amide groups of the receptor of 1 played an important role for the binding with In(III). Moreover, 1 was suitable for the ratiometric detection of In(III) in tap water and groundwater. 1 showed much better detection properties than those of the colorimetric methods using EDTA with Eriochrome black T (EBT) and 4-(2-pyridylazo) resorcinol (PAR) for the detection of In(III) in tap water and groundwater.
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BACKGROUND: To investigate characteristics of biofilm which is usually found in silicone tube for nasolacrimal duct surgery and can be the root of chronic bacterial infections eventually resulted in surgical failure. METHODS: To form a biofilm, sterile silicone tube was placed in culture media of Staphylococcus aureus, Corynebacterium matruchotii, Pseudomonas aeruginosa, or Streptococcus pneumonia. Biofilms formed on these silicone tubes were fixed with 95% ethanol and stained with 0.1% crystal violet. After staining, the optical densities of biofilms were measured using spectrophotometer on a weekly basis for 12 weeks. RESULTS: Staphylococcus aureus group and Pseudomonas aeruginosa group formed significantly more amounts of biofilms compared to the control group. The maximum optical densities of the two groups were found on week 3-4 followed by a tendency of decrease afterwards. However, the amounts of biofilms formed in other groups of silicone tubes were not statistically significant from that of the control group. CONCLUSIONS: Bacterial species that could form biofilm on silicone tube included Staphylococcus aureus (week 3) and Pseudomonas aeruginosa (Week 4). It is important to first consider that the cause of infection around 1 month after silicone tube intubation can be Staphylococcus aureus and Pseudomonas aeruginosa.
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Biofilmes/crescimento & desenvolvimento , Dacriocistorinostomia/instrumentação , Bactérias Gram-Positivas/fisiologia , Pseudomonas/isolamento & purificação , Stents/microbiologia , Análise de Variância , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Ducto Nasolacrimal/cirurgia , Silicones , Especificidade da EspécieRESUMO
Active control of light-matter interactions in semiconductors is critical for realizing next generation optoelectronic devices with real-time control of the system's optical properties and hence functionalities via external fields. The ability to dynamically manipulate optical interactions by applied fields in active materials coupled to cavities with fixed geometrical parameters opens up possibilities of controlling the lifetimes, oscillator strengths, effective mass, and relaxation properties of a coupled exciton-photon (or plasmon) system. Here, we demonstrate electrical control of exciton-plasmon coupling strengths between strong and weak coupling limits in a two-dimensional semiconductor integrated with plasmonic nanoresonators assembled in a field-effect transistor device by electrostatic doping. As a result, the energy-momentum dispersions of such an exciton-plasmon coupled system can be altered dynamically with applied electric field by modulating the excitonic properties of monolayer MoS2 arising from many-body effects. In addition, evidence of enhanced coupling between charged excitons (trions) and plasmons was also observed upon increased carrier injection, which can be utilized for fabricating Fermionic polaritonic and magnetoplasmonic devices. The ability to dynamically control the optical properties of a coupled exciton-plasmonic system with electric fields demonstrates the versatility of the coupled system and offers a new platform for the design of optoelectronic devices with precisely tailored responses.
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BACKGROUND: To investigate the antibiofilm efficacy of nitric oxide (NO) on soft contact lenses. METHODS: Nitrite (NO precursor) release from various concentrations (0-1000 µM) of sodium nitrite (NaNO2, NO donor) was measured by Griess Assay. Cell viability assay was performed using human corneal epithelial cell under various concentration (0-1000 µM) of NaNO2. Biofilm formation on soft contact lenses was achieved by adding Staphylococcus aureus or Pseudomonas aeruginosa to the culture media. Various concentrations of NaNO2 (0-1000 µM) were added to the culture media, each containing soft contact lens. After incubation in NaNO2 containing culture media for 1, 3, or 7 days, each contact lens was transferred to a fresh, bacteria-free media without NaNO2. The bacteria in the biofilm were dispersed in the culture media for planktonic growth. After reculturing the lenses in the fresh media for 24 h, optical density (OD) of media was measured at 600 nm and colony forming unit (CFU) was counted by spreading media on tryptic soy agar plate for additional 18 h. RESULTS: Nitrite release from NaNO2 showed dose-dependent suppressive effect on biofilm formation. Most nitrite release from NaNO2 tended to occur within 30 min. The viability of human corneal epithelial cells was well maintained at tested NaNO2 concentrations. The bacterial CFU and OD showed dose-dependent decrease in the NaNO2 treated samples on days 1, 3 and 7 for both Staphylococcus aureus and Pseudomonas aeruginosa. CONCLUSIONS: NO successfully inhibited the biofilm formation by Staphylococcus aureus or Pseudomonas aeruginosa on soft contact lenses in dose-dependent manner.
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Biofilmes/efeitos dos fármacos , Lentes de Contato Hidrofílicas/microbiologia , Óxido Nítrico/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Análise de Variância , Biofilmes/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Infecções Oculares Bacterianas/prevenção & controle , HumanosRESUMO
We demonstrate strong exciton-plasmon coupling in silver nanodisk arrays integrated with monolayer MoS2 via angle-resolved reflectance microscopy spectra of the coupled system. Strong exciton-plasmon coupling is observed with the exciton-plasmon coupling strength up to 58 meV at 77 K, which also survives at room temperature. The strong coupling involves three types of resonances: MoS2 excitons, localized surface plasmon resonances (LSPRs) of individual silver nanodisks and plasmonic lattice resonances of the nanodisk array. We show that the exciton-plasmon coupling strength, polariton composition, and dispersion can be effectively engineered by tuning the geometry of the plasmonic lattice, which makes the system promising for realizing novel two-dimensional plasmonic polaritonic devices.
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PURPOSE: The purpose of this study was to compare a viscoelastic foam overlay (VEFO) to a standard hospital mattress for pressure injury (PI) prevention. We also compared interface pressures (IPs) of the VEFO to our facility's standard hospital mattress. DESIGN: Prospective, randomized controlled trial. SUBJECTS AND SETTING: Data analysis was based on 110 participants (55 in each group) who were 19 years or older, had a Braden Scale for Pressure Sore Risk score of 16 or less, and were cared for on a neurology, oncology, or pulmonology inpatient care unit. The research setting was the Samsung Medical Center in Seoul, South Korea. METHODS: Participants were divided into 2 groups: the experimental group were based on a VEFO on top of the standard hospital mattress used in our facility. Participants in the control group were placed on a standard hospital mattress with/without air overlay. All patients were given standard nursing care for prevention of PI. Skin assessments were completed daily over a period of 2 weeks. In addition, we compared IPs of the standard hospital mattress and the VEFO in participants randomly allocated to the intervention group. Interface pressure was measured over the sacral/coccygeal area with subjects in the supine position. Pressures were measured immediately before and immediately following placement of the VEFO and just before data collection began. Data were collected between October 2013 and November 2014. Pressure injury incidence was compared between groups using the χ test, and IPs were compared using the paired t test. INSTRUMENTS: Pressure injury development was determined using the staging system described in guidelines from the National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel, and Pan Pacific Pressure Injury Alliance in 2014. Interface pressure was measured using a device manufactured for this purpose. RESULTS: The incidence of PI development was significantly lower in subjects assigned to the experimental group as compared to those in the control group (3.6%-27.3% over the 2-week data collection period; P = .001). The maximum IP was significantly lower on the VEFO with standard hospital mattress than on the standard hospital mattress (paired t = 8.87, P < .001). CONCLUSIONS: Patients managed with a VEFO had a significantly lower incidence of PI than those managed with a standard hospital mattress. Additional research is needed to further characterize the efficacy of the VEFO, its effect on PI healing, and its effect of PI prevention in high-risk populations such as critically ill patients.
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Bandagens/normas , Estado Terminal/terapia , Úlcera por Pressão/prevenção & controle , Substâncias Viscoelásticas/farmacologia , Idoso , Idoso de 80 Anos ou mais , Roupas de Cama, Mesa e Banho/normas , Feminino , Humanos , Doença Iatrogênica/prevenção & controle , Incidência , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , República da Coreia , Fatores de Risco , Substâncias Viscoelásticas/uso terapêuticoRESUMO
UNLABELLED: In Kaposi's sarcoma-associated herpesvirus (KSHV), poly(ADP-ribose) polymerase 1 (PARP-1) acts as an inhibitor of lytic replication. Here, we demonstrate that KSHV downregulated PARP-1 upon reactivation. The viral processivity factor of KSHV (PF-8) interacted with PARP-1 and was sufficient to degrade PARP-1 in a proteasome-dependent manner; this effect was conserved in murine gammaherpesvirus 68. PF-8 knockdown in KSHV-infected cells resulted in reduced lytic replication upon reactivation with increased levels of PARP-1, compared to those in control cells. PF-8 overexpression reduced the levels of the poly(ADP-ribosyl)ated (PARylated) replication and transcription activator (RTA) and further enhanced RTA-mediated transactivation. These results suggest a novel viral mechanism for overcoming the inhibitory effect of a host factor, PARP-1, thereby promoting the lytic replication of gammaherpesvirus. IMPORTANCE: Gammaherpesviruses are important human pathogens, as they are associated with various kinds of tumors and establish latency mainly in host B lymphocytes. Replication and transcription activator (RTA) of Kaposi's sarcoma-associated herpesvirus (KSHV) is a central molecular switch for lytic replication, and its expression is tightly regulated by many host and viral factors. In this study, we investigated a viral strategy to overcome the inhibitory effect of poly(ADP-ribose) polymerase 1 (PARP-1) on RTA's activity. PARP-1, an abundant multifunctional nuclear protein, was downregulated during KSHV reactivation. The viral processivity factor of KSHV (PF-8) directly interacted with PARP-1 and was sufficient and necessary to degrade PARP-1 protein in a proteasome-dependent manner. PF-8 reduced the levels of PARylated RTA and further promoted RTA-mediated transactivation. As this was also conserved in another gammaherpesvirus, murine gammaherpesvirus 68, our results suggest a conserved viral modulation of a host inhibitory factor to facilitate its lytic replication.
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Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Herpesvirus Humano 8/fisiologia , Poli(ADP-Ribose) Polimerases/biossíntese , Proteínas Virais/metabolismo , Replicação Viral/fisiologia , Animais , Cricetinae , Células HEK293 , Humanos , Camundongos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Rhadinovirus/fisiologia , Proteínas Virais/genéticaRESUMO
The suppressor of cytokine signaling 2 (SOCS2) has been reported to be involved in astroglial reactions and adult neurogenesis in the ischemic hippocampus. To elucidate whether SOCS2 is implicated in the pathophysiology of stroke, we investigate spatiotemporal regulation and identification of cell phenotypes expressing SOCS2 after transient focal cerebral ischemia. Weak hybridization signals for SOCS2 mRNA were constitutively observed in striatal neurons and upregulation of SOCS2 mRNA was induced in association with nestin-positive cells in stroke-lesioned rats. Analysis of the characteristics and phenotypes of SOCS2/nestin double-labeled cells revealed spatial differences between infarct and peri-infarct areas. SOCS2/nestin double-labeled cells in the infarct area were associated with the vasculature and were highly proliferative. In contrast, the double-labeled cells in the peri-infarct area were indeed glial fibrillary acidic protein (GFAP)-positive reactive astrocytes forming the glial scar, although nestin-negative reactive astrocytes also exhibited weak SOCS2 expression. In addition, induction of SOCS2 expression was observed in Iba1-positive cells showing a macrophage-like phenotype with amoeboid morphology; these cells were predominantly localized in the infarct area. In the peri-infarct area, only a small proportion of Iba1-positive cells with the morphology of brain macrophages expressed SOCS2 and most activated stellate microglial cells with thick and short processes exhibited weak or negligible SOCS2 expression. Thus, our results revealed the phenotypic and functional heterogeneity of SOCS2-expressing cells within infarct and peri-infarct areas, suggesting the involvement of SOCS2 in astroglial reactions and activation/recruitment of brain macrophages and its potential role in perivascular progenitors/stem cells after ischemic stroke.
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The manipulation of light-matter interactions in two-dimensional atomically thin crystals is critical for obtaining new optoelectronic functionalities in these strongly confined materials. Here, by integrating chemically grown monolayers of MoS2 with a silver-bowtie nanoantenna array supporting narrow surface-lattice plasmonic resonances, a unique two-dimensional optical system has been achieved. The enhanced exciton-plasmon coupling enables profound changes in the emission and excitation processes leading to spectrally tunable, large photoluminescence enhancement as well as surface-enhanced Raman scattering at room temperature. Furthermore, due to the decreased damping of MoS2 excitons interacting with the plasmonic resonances of the bowtie array at low temperatures stronger exciton-plasmon coupling is achieved resulting in a Fano line shape in the reflection spectrum. The Fano line shape, which is due to the interference between the pathways involving the excitation of the exciton and plasmon, can be tuned by altering the coupling strengths between the two systems via changing the design of the bowties lattice. The ability to manipulate the optical properties of two-dimensional systems with tunable plasmonic resonators offers a new platform for the design of novel optical devices with precisely tailored responses.
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Dissulfetos/química , Molibdênio/química , Nanoestruturas/química , Prata/química , Luz , Análise Espectral Raman , Ressonância de Plasmônio de SuperfícieRESUMO
Krüppel-like factor 4 (KLF4) is a transcription factor with diverse and cell type-specific functions and is associated with a variety of pathophysiological processes. Recently, it has been proposed that the regulation of KLF4 is critical to neuronal differentiation and that neural progenitors overexpressing KLF4 take on a glial identity. The present study aimed to determine whether KLF4 is involved in the astroglial reaction induced by ischemia-reperfusion injury in the brain. No specific KLF4 immunoreactivity was observed in resting astrocytes of the control hippocampus, but significant induction was detected in reactive astrocytes preferentially located in the CA1 and dentate hilar regions of the hippocampus following transient forebrain ischemia. Astroglial KLF4 expression was induced in the nuclei and cytoplasm within 3 days of ischemia and persisted for at least 4 weeks. This pattern was reproduced in an in vitro astrogliosis model of rat primary cortical astrocytes exposed to oxygen-glucose deprivation (OGD). Furthermore, immunoblot assay showed that nuclear and cytosolic extracts from cortical astrocytes subjected to OGD had significantly higher levels of KLF4 protein compared to normoxic extracts. Thus, our data demonstrate that KLF4 expression was induced in astroglia by ischemic injury both in vivo and in vitro, suggesting that KLF4 may act as a transcription factor linked to the regulation of the astroglial reaction following ischemic injury.
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Astrócitos/patologia , Hipóxia-Isquemia Encefálica/patologia , Fatores de Transcrição Kruppel-Like/biossíntese , Animais , Região CA1 Hipocampal/patologia , Hipóxia Celular , Células Cultivadas , Giro Denteado/patologia , Glucose/deficiência , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Masculino , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-DawleyRESUMO
Ellobium chinense is an airbreathing, pulmonate gastropod species that inhabits saltmarshes in estuaries of the northwestern Pacific. Due to a rapid population decline and their unique ecological niche in estuarine ecosystems, this species has attracted special attention regarding their conservation and the genomic basis of adaptation to frequently changing environments. Here we report a draft genome assembly of E. chinense with a total size of 949.470 Mb and a scaffold N50 of 1.465 Mb. Comparative genomic analysis revealed that the GO terms enriched among four gastropod species are related to signal transduction involved in maintaining electrochemical gradients across the cell membrane. Population genomic analysis using the MSMC model for 14 re-sequenced individuals revealed a drastic decline in Korean and Japanese populations during the last glacial period, while the southern Chinese population retained a much larger effective population size (Ne). These contrasting demographic changes might be attributed to multiple environmental factors during the glacial-interglacial cycles. This study provides valuable genomic resources for understanding adaptation and historical demographic responses to climate change.