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Introduction: There is no useful method to discriminate between latent tuberculosis infection (LTBI) and active pulmonary tuberculosis (PTB). This study aimed to investigate the potential of cytokine profiles to discriminate between LTBI and active PTB using whole-blood stimulation with Mycobacterium tuberculosis (MTB) antigens, including latency-associated antigens. Materials and methods: Patients with active PTB, household contacts of active PTB patients and community exposure subjects were recruited in Manila, the Philippines. Peripheral blood was collected from the participants and used for whole-blood stimulation (WBS) with either the early secretory antigenic target and the 10-kDa culture filtrate protein (ESAT-6/CFP-10), Rv3879c or latency-associated MTB antigens, including mycobacterial DNA-binding protein 1 (MDP-1), α-crystallin (Acr) and heparin-binding hemagglutinin (HBHA). Multiple cytokine concentrations were analyzed using the Bio-Plex™ multiplex cytokine assay. Results: A total of 78 participants consisting of 15 active PTB patients, 48 household contacts and 15 community exposure subjects were eligible. The MDP-1-specific IFN-γ level in the active PTB group was significantly lower than that in the household contact group (p < 0.001) and the community exposure group (p < 0.001). The Acr-specific TNF-α and IL-10 levels in the active PTB group were significantly higher than those in the household contact (TNF-α; p = 0.001, IL-10; p = 0.001) and community exposure (TNF-α; p < 0.001, IL-10; p = 0.01) groups. However, there was no significant difference in the ESAT-6/CFP-10-specific IFN-γ levels among the groups. Conclusion: The patterns of cytokine profiles induced by latency-associated MTB antigens using WBS have the potential to discriminate between LTBI and active PTB. In particular, combinations of IFN-γ and MDP-1, TNF-α and Acr, and IL-10 and Acr are promising. This study provides the first demonstration of the utility of MDP-1-specific cytokine responses in WBS.
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Antígenos Bacterianos , Citocinas , Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/sangre , Masculino , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/inmunología , Tuberculosis Latente/sangre , Tuberculosis Latente/microbiología , Femenino , Mycobacterium tuberculosis/inmunología , Filipinas , Adulto , Citocinas/sangre , Persona de Mediana Edad , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología , Adulto Joven , Proteínas Bacterianas/inmunologíaRESUMEN
[This corrects the article DOI: 10.3389/fimmu.2023.1222428.].
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Introduction: Controlling pulmonary Mycobacterium avium complex (MAC) disease is difficult because there is no way to know the clinical stage accurately. There have been few attempts to use cell-mediated immunity for diagnosing the stage. The objective of this study was to characterize cytokine profiles of CD4+T and CD19+B cells that recognize various Mycobacterium avium-associated antigens in different clinical stages of MAC. Methods: A total of 47 MAC patients at different stages based on clinical information (14 before-treatment, 16 on-treatment, and 17 after-treatment) and 17 healthy controls were recruited. Peripheral blood mononuclear cells were cultured with specific antigens (MAV0968, 1160, 1276, and 4925), and the cytokine profiles (IFN-γ, TNF-α, IL-2, IL-10, IL-13, and IL-17) of CD4+/CD3+ and CD19+ cells were analyzed by flow cytometry. Results: The response of Th1 cytokines such as IFN-γ and TNF-α against various antigens was significantly higher in both the on-treatment and after-treatment groups than in the before-treatment group and control (P < 0.01-0.0001 and P < 0.05-0.0001). An analysis of polyfunctional T cells suggested that the presence of IL-2 is closely related to the stage after the start of treatment (P = 0.0309-P < 0.0001) and is involved in memory function. Non-Th1 cytokines, such as IL-10 and IL-17, showed significantly higher responses in the before-treatment group (P < 0.0001 and P < 0.01-0.0001). These responses were not observed with purified protein derivative (PPD). CD19+B cells showed a response similar to that of CD4+T cells. Conclusion: There is a characteristic cytokine profile at each clinical stage of MAC.
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Enfermedades Pulmonares , Infección por Mycobacterium avium-intracellulare , Humanos , Complejo Mycobacterium avium , Interleucina-10 , Interleucina-17 , Interleucina-2/uso terapéutico , Factor de Necrosis Tumoral alfa/uso terapéutico , Leucocitos Mononucleares , CitocinasRESUMEN
Septic shock is characterized by dysregulated vascular permeability. We hypothesized that the vascular permeability of endothelial cells (ECs) would be regulated by serotonin via serotonin-Rho-associated kinase (ROCK) signaling. We aimed to determine the impact of 5-hydroxyindoleacetic acid (5-HIAA) on septic shock as a novel biomarker. Plasma 5-HIAA levels and disease severity indices were obtained from 47 patients with sepsis. The association between 5-HIAA levels and severity indices was analyzed. Permeability upon serotonin stimulation was determined using human pulmonary microvascular ECs. 5-HIAA were significantly higher in septic shock patients than in patients without shock or healthy controls (p = 0.004). These elevated levels were correlated with severity indexes (SOFA score [p < 0.001], APACHE II [p < 0.001], and PaO2:FiO2 [p = 0.02]), and longitudinally associated with worse clinical outcomes (mechanical ventilation duration [p = 0.009] and ICU duration [p = 0.01]). In the experiment, serotonin increased the permeability of ECs, which was inhibited by the ROCK inhibitor (p < 0.001). Serotonin increases vascular permeability of ECs via ROCK signaling. This suggests a novel mechanism by which serotonin disrupts endothelial barriers via ROCK signaling and causes the pathogenesis of septic shock with a vascular leak. Serotonin serves as a novel biomarker of vascular permeability.
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Indoles/sangre , Serotonina/metabolismo , Choque Séptico/sangre , Quinasas Asociadas a rho/genética , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Permeabilidad Capilar/genética , Células Endoteliales/metabolismo , Células Endoteliales/patología , Femenino , Humanos , Masculino , Choque Séptico/metabolismo , Choque Séptico/patologíaRESUMEN
BACKGROUND: A pneumatocele is a transient thin-walled lesion and rare complication in adult pneumonia. A variety of infectious pathogens have been reported in children with pneumatoceles. We report the first case of adult pneumonia with pneumatocele formation that is likely caused by Streptococcus pyogenes and coinfection with influenza A virus. CASE PRESENTATION: A 64-year-old Japanese man presented with a one-week history of fever, sore throat, and arthralgia. He was referred to our university hospital for respiratory distress. He required mechanical ventilation in the intensive care unit (ICU). Bacterial culture detected S. pyogenes in the bronchoscopic aspirates, which was not detected in blood. Although a rapid influenza antigen test was negative, an influenza A polymerase chain reaction (PCR) test was positive. Therefore, he was diagnosed with coinfection of influenza A and group A streptococcus (GAS) pneumonia complicated by probable streptococcal toxic shock syndrome. A chest radiograph on admission showed diffuse patchy opacification and consolidation in the bilateral lung fields. Multiple thin-walled cysts appeared in both middle lung fields on computed tomography (CT). On the following day, the bilateral cysts had turned into a mass-like opacity. The patient died despite intensive care. An autopsy was performed. The pathology investigation revealed multiple hematomas formed by bleeding in pneumatoceles. CONCLUSIONS: There have been no previous reports of a pneumatocele complicated by S. pyogenes in an adult patient coinfected with influenza A. Further molecular investigation revealed that the S. pyogenes isolate had the sequence type of emm3.
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Coinfección , Gripe Humana/complicaciones , Gripe Humana/patología , Enfermedades Pulmonares/etiología , Neumonía/complicaciones , Infecciones Estreptocócicas/complicaciones , Infecciones Estreptocócicas/patología , Coinfección/complicaciones , Coinfección/patología , Quistes/diagnóstico por imagen , Resultado Fatal , Humanos , Virus de la Influenza A , Gripe Humana/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/patología , Masculino , Persona de Mediana Edad , Neumonía/diagnóstico por imagen , Neumonía/microbiología , Neumonía/patología , Choque Séptico/diagnóstico , Infecciones Estreptocócicas/diagnóstico por imagen , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes , Tomografía Computarizada por Rayos XRESUMEN
Impaired efferocytosis is a key mechanism of inflammatory lung diseases, including chronic obstructive pulmonary disease and cystic fibrosis. Cigarette smoking activates RhoA and impairs efferocytosis in alveolar macrophages, but the mechanism has not been fully elucidated. We investigated the role of endoplasmic reticulum (ER) stress induced by cigarette smoking in the disruption of efferocytosis. Both tunicamycin (10 µg/ml) and thapsigargin (0.1 and 1 µM), which are ER stress inducers, suppressed efferocytosis in J774 cells, and a Rho-associated coiled-coil-forming kinase (ROCK) inhibitor (Y27632) reversed this effect. We validated the effect of tunicamycin on efferocytosis in experiments using RAW264.7 cells. Then, we investigated the role of the unfolded protein response (UPR) in efferocytosis impaired by ER stress. A PERK inhibitor (GSK2606414) restored the efferocytosis that had been impaired by TM, and an eIF2α dephosphorylation inhibitor (salubrinal) suppressed efferocytosis. Cigarette smoke extract (CSE) induced ER stress in J774 macrophages and RhoA activation in J774 cells, and the CSE-induced ROCK activity was successfully reversed by GSK2606414 and tauroursodeoxycholic acid. Finally, we confirmed that ER stress suppresses efferocytosis in murine alveolar macrophages and that GSK2606414 could rescue this process. These data suggest that cigarette smoke-induced ER stress and the UPR play crucial roles in RhoA activation and suppression of efferocytosis in the lung.
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Fumar Cigarrillos/efectos adversos , Estrés del Retículo Endoplásmico , Macrófagos/patología , Fagocitosis , Proteína de Unión al GTP rhoA/metabolismo , Adenina/análogos & derivados , Adenina/farmacología , Animales , Línea Celular , Estrés del Retículo Endoplásmico/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Factor 2 Eucariótico de Iniciación/metabolismo , Femenino , Indoles/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos ICR , Modelos Biológicos , Fagocitosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ácido Tauroquenodesoxicólico/farmacología , Tunicamicina/farmacología , eIF-2 Quinasa/metabolismo , Quinasas Asociadas a rho/metabolismoRESUMEN
Mycobacterium tuberculosis (M. tuberculosis) produces a diverse range of antigenic proteins in its dormant phase. The cytokine profiles of CD4+ T cell responses, especially subsets other than Th1 type (non-Th1 type), against these latency-associated M. tuberculosis antigens such as α-crystallin (Acr), heparin-binding hemagglutinin (HBHA), and mycobacterial DNA-binding protein 1 (MDP-1) remain elusive in relation to the clinical stage of M. tuberculosis infection. In the present study, peripheral blood mononuclear cells (PBMCs) collected from different stages of M. tuberculosis-infected cases and control PBMCs were stimulated with these antigens and ESAT-6/CFP-10. Cytokine profiles of CD4+ T cells were evaluated by intracellular cytokine staining using multicolor flow cytometry. Our results demonstrate that Th1 cytokine responses were predominant after TB onset independent of the type of antigen stimulation. On the contrary, non-Th1 cytokine responses were preferentially induced by latency-associated M. tuberculosis antigens, specifically IL-10 response against Acr in latent M. tuberculosis infection. From these results, we surmise a shift in the CD4+ T cell response from mixed non-Th1 to Th1 dominant type during TB progression.
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Antígenos Bacterianos/inmunología , Linfocitos T CD4-Positivos/inmunología , Tuberculosis Latente/inmunología , Mycobacterium tuberculosis/inmunología , Células TH1/inmunología , Adulto , Linfocitos T CD4-Positivos/metabolismo , Estudios de Casos y Controles , Citocinas/metabolismo , Femenino , Humanos , Tuberculosis Latente/metabolismo , Tuberculosis Latente/microbiología , Masculino , Persona de Mediana Edad , Células TH1/metabolismo , Adulto JovenRESUMEN
OBJECTIVE: Diabetes mellitus (DM) patients are susceptible to delayed resolution of pneumonia. However, the pathogenesis of the impaired tissue repair in inflamed lungs in diabetic patients is unknown. We evaluated phagocytosis of apoptotic cells (efferocytosis), hepatocyte growth factor (HGF) production in bronchoalveolar lavage fluid (BALF), and lung histology in the resolution phase following acute lung injury in streptozotocin (STZ)-induced ß-cell-depleted hyperglycemic mice. We also investigated efferocytosis and HGF production by macrophages under ß-cell depletion condition ex vivo. RESULTS: In ß-cell-depleted mice, efferocytosis was not significantly different from that in control mice; however, the concentration of HGF in BALF was decreased. In addition, diminished HGF production by alveolar macrophages and DNA synthesis in the alveolar epithelium was observed by immunohistochemistry. Ex vivo experiments confirmed that HGF production by macrophages was impaired under ß-cell depletion probably because of endoplasmic reticulum stress.
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Linfocitos B , Líquido del Lavado Bronquioalveolar , Citofagocitosis , Diabetes Mellitus Experimental/complicaciones , Estrés del Retículo Endoplásmico , Factor de Crecimiento de Hepatocito/metabolismo , Macrófagos Alveolares/metabolismo , Neumonía/inmunología , Neumonía/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos ICR , Neumonía/etiologíaRESUMEN
Lung abscess is usually treated with long-term antibiotic therapy. Due to the lack of a safe and easy drainage technique, drainage is only applied in refractory cases. We herein describe three cases in which drainage was successfully performed by endobronchial ultrasonography using a modified guide sheath. This procedure may have advantages in the detection of causative pathogens and early infection source control, and may therefore lead to the appropriate selection of antibiotics and reduce the duration of antibiotic therapy.
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Broncoscopía/métodos , Drenaje/métodos , Absceso Pulmonar/cirugía , Ultrasonografía Intervencional/métodos , Adulto , Anciano , Drenaje/instrumentación , Femenino , Humanos , Absceso Pulmonar/diagnóstico por imagen , Masculino , Persona de Mediana EdadRESUMEN
Corynebacterium ulcerans infection was recently recognized as a zoonosis. We present 2 cases of severe pneumonia complicated by diffuse pseudomembrane formation on the bronchus caused by C. ulcerans-producing diphtheria toxin. Our purpose is to alert medical professionals to the virulence of Corynebacterium species other than C. diphtheriae.
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Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/microbiología , Corynebacterium/clasificación , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/microbiología , Anciano , Antibacterianos/uso terapéutico , Biomarcadores , Corynebacterium/genética , Infecciones por Corynebacterium/tratamiento farmacológico , Endoscopía , Femenino , Humanos , Neumonía Bacteriana/tratamiento farmacológico , Radiografía Torácica , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Trifluoromethylphenyl-substituted phthalimide derivatives favorably form triboluminescence (TL) active noncentrosymmetric crystals. Oligothienyl-, oligophenyl-, and naphthyl-substituted phthalimide derivatives were successfully developed as a series of metal free TL compounds. X-ray crystal structure analyses of bithienyl and naphthyl derivatives revealed noncentrosymmetric layer structures in the same direction. Introduction of suitable electron rich π-units such as thienyl groups enhances their photoluminescence and TL characteristics, and the colors can be also controlled in the visible region. A rigid naphthyl-substituted imide derivative exhibits extremely high TL performance.
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A Pd-catalyzed single-step C-H arylation of dioxythiophene derivatives bearing unprotected reactive functional groups (-OH, -COOH, -N3) in a phosphine-free manner has been developed. Various dioxythiopene-based oligoarenes with extended π-conjugation are obtained with good yields (up to 90%). These oligoarenes display suitable optical properties (absorption and emission maxima, quantum yields) and contain reactive functional groups suitable for further conjugations with bioactive molecules. This new methodology is step economical (fewer synthetic steps) and environmentally friendly (no toxic metal-containing by-products) and the oligoarenes synthesized are potentially applicable for bio-labeling, bioimaging, and biosensing.
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Although electrically stimulated neurite outgrowth on bioelectronic devices is a promising means of nerve regeneration, immunogenic scar formation can insulate electrodes from targeted cells and tissues, thereby reducing the lifetime of the device. Ideally, an electrode material capable of electrically interfacing with neurons selectively and efficiently would be integrated without being recognized by the immune system and minimize its response. Here we develop a cell membrane-mimicking conducting polymer possessing several attractive features. This polymer displays high resistance towards nonspecific enzyme/cell binding and recognizes targeted cells specifically to allow intimate electrical communication over long periods of time. Its low electrical impedance relays electrical signals efficiently. This material is capable to integrate biochemical and electrical stimulation to promote neural cellular behaviour. Neurite outgrowth is enhanced greatly on this new conducting polymer; in addition, electrically stimulated secretion of proteins from primary Schwann cells can also occur on it.
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Materiales Biocompatibles/química , Materiales Biomiméticos/química , Neuritas/fisiología , Animales , Adhesión Celular , Conductividad Eléctrica , Estimulación Eléctrica , Diseño de Equipo , Ratones , Células 3T3 NIH , Factor de Crecimiento Nervioso/metabolismo , Neuronas/fisiología , Células PC12 , Péptidos/química , Polímeros/química , Ratas , Células de SchwannRESUMEN
We have developed methods for installing aryl substituents directly on the phosphino groups of the 1,3-diphosphacyclobutane-2,4-diyl system. The aryl substituents tuned the electronic and structural characteristics of the biradical unit both in solution and in the solid state. 1-tert-butyl-2,4-bis(2,4,6-tri-tert-butylphenyl)-1,3-diphosphacyclobuten-4-yl anion, prepared from phosphaalkyne (Mes*C≡P; Mes* = 2,4,6-tBu3C6H2) and t-butyllithium, was allowed to react with an electron-deficient N-heterocyclic reagent. The corresponding N-heteroaryl-substituted P-heterocyclic biradicals were produced via SNAr reactions. Biradicals bearing perfluorinated pyridyl substituents exhibited photoabsorption properties comparable to those of previously reported derivatives because the highest occupied and lowest unoccupied molecular orbit levels were reduced by a similar amount. In contrast, the triazine substituent reduced the band gap of the biradical unit, and the large red shift in the visible absorption and high oxidation potential were further tuned via subsequent SNAr and Negishi coupling reactions. The amino-substituted triazine structure provided a strongly electron-donating biradical chromophore, which produced unique p-type semiconducting behavior even though there was no obvious π-overlap in the crystalline state. The single-electron transfer reaction involving Mes*C≡P, phenyllithium, and iodine afforded 1,3-diphenyl-2,4-bis(2,4,6-tri-tert-butylphenyl)-1,3-diphosphacyclobutane-2,4-diyl via the intermediate P-heterocyclic monoradical. The tetraaryl-substituted symmetric biradical product was used to determine the electron density distribution from the X-ray diffraction data. The data show highly localized radicalic electrons around the skeletal carbon atoms, moderately polarized skeletal P-C bonds in the four-membered ring, and no covalent transannular interaction.
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Compuestos Heterocíclicos/química , Compuestos Organofosforados/química , Aire , Electrones , Radicales Libres/síntesis química , Radicales Libres/química , Compuestos Heterocíclicos/síntesis química , Modelos Moleculares , Estructura Molecular , Teoría CuánticaRESUMEN
Although IFN-γ release assays (IGRAs) provide increased specificity over tuberculin skin tests, the early and sensitive detection of reactivation of latently infected Mycobacterium tuberculosis is required to control tuberculosis (TB). Recently, a multicolor flow cytometry has been developed to study CD4(+) T cell cytokine responses (IFN-γ/IL-2/TNF-α) to purified protein derivatives (PPD) and M. tuberculosis-specific antigens (ESAT-6/CFP-10) and provided useful information regarding anti-TB immunity. However, the diagnostic relevancy remains uncertain. Here, we analyzed three additional CD4(+) T cell cytokine responses (IL-10/IL-13/IL-17) to latent mycobacterial antigens (α-crystallin, methylated heparin-binding hemagglutinin [HBHA], and mycobacterial DNA-binding protein 1 [MDP-1]) as well as PPD and ESAT-6/CFP-10 in 12 IGRA(+) TB cases and 8 healthy controls. No significant difference in IFN-γ response was observed between TB cases and controls, which was likely due to the high variation among the individuals. However, we found a significant increase over healthy controls in (i) the IL-2 response to HBHA in recovery stage TB cases, (ii) the number of M. tuberculosis-specific polyfunctional CD4(+) T cells in on-treatment and recovery stage cases, and (iii) the IL-17 response to HBHA and MDP-1 in on-treatment and recovery stage cases. These results suggest that a combination of these T cell cytokine parameters could aid in accurate diagnosis of latent TB infection.
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Antígenos Bacterianos/inmunología , Linfocitos T CD4-Positivos/inmunología , Citocinas/biosíntesis , Citometría de Flujo/métodos , Tuberculosis Latente/diagnóstico , Mycobacterium tuberculosis/inmunología , Coloración y Etiquetado/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Color , Femenino , Colorantes Fluorescentes/análisis , Humanos , Tuberculosis Latente/inmunología , Masculino , Persona de Mediana EdadRESUMEN
Tailoring the surface of biometallic implants with protein-resistant polymer brushes represents an efficient approach to improve the biocompability and mechanical compliance with soft human tissues. A general approach utilizing electropolymerization to form initiating group (-Br) containing poly(3,4-ethylenedioxythiophen)s (poly(EDOT)s) is described. After the conducting polymer is deposited, neutral poly((oligo(ethylene glycol) methacrylate), poly(OEGMA), and zwitterionic poly([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide), poly(SBMA), brushes are grafted by surface-initiated atom transfer radical polymerization. Quartz crystal microbalance (QCM) experiments confirm protein resistance of poly(OEGMA) and poly(SBMA)-grafted poly(EDOT)s. The protein binding properties of the surface are modulated by the density of polymer brushes, which is controlled by the feed content of initiator-containing monomer (EDOT-Br) in the monomer mixture solution for electropolymerization. Furthermore, these polymer-grafted poly(EDOT)s also prevent cells to adhere on the surface.
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Materiales Biocompatibles/química , Técnicas Biosensibles/métodos , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Adhesión Celular/fisiología , Polímeros/química , Proteínas/química , Animales , Bromo/química , Espectroscopía Dieléctrica , Enzimas/química , Humanos , Ratones , Microscopía de Fuerza Atómica , Células 3T3 NIH/citología , Resonancia Magnética Nuclear Biomolecular , Prótesis e Implantes , Tecnicas de Microbalanza del Cristal de Cuarzo , Oligoelementos/químicaRESUMEN
π-Conjugated systems 2a and 2b containing thiophene-fused DCNQI with long alkyl and trifluoromethylphenyl groups were synthesized as potential active materials for solution-processed and air-stable n-type organic thin-film transistors (OTFTs). The electrochemical measurements revealed that the lowest unoccupied molecular orbital (LUMO) of the compounds have an energy level less than -4.0 eV, indicating air stable n-type materials. The long alkyl groups endowed the compounds good solubility and solution-processability. X-ray diffraction measurements revealed the difference of the molecular arrangement depending on the alkyl groups, which were also observed in the UV-vis absorptions of the films. A relatively good mobility up to 0.003 cm(2) V(-1) s(-1) for 2a by spin-coating was obtained with good air stability.
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Fused polycyclic indeno[1,2-b]fluorene derivatives with aryl substituents at the 6,12-positions have been prepared as a potential antiaromatic 20π electronic system. They showed strong absorptions in the visible region and amphoteric redox properties. The quinoid-type molecular structures were revealed by X-ray crystal-structure analysis, which indicated that the bond lengths of the quinoid unit depend on the aryl substituents. Whereas nucleus-independent chemical shift NICS(1) calculations indicate the antiaromatic nature of the s-indacene core, they have higher stability than substituted acene derivatives. The derivatives with difluorophenyl or anthryl groups were stable in solution. Vapor-deposited thin films showed ambipolar carrier transportation in the field-effect transistor devices.
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Organic field-effect transistors with hydrogen-bonded diketopyrrolopyrrole-thiophene co-oligomers were fabricated by a solution-process method with annealing at 200 °C, showing ambipolar charge-carrier transfer with field-effect mobilities up to µ(h) = 6.7 × 10(-3) cm(2) V(-1)s(-1) and µ(e) = 5.6 × 10(-3) cm(2) V(-1) s(-1).