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1.
Scand J Immunol ; : e13372, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654426

RESUMEN

Chronic granulomatous disease (CGD) is a primary immunodeficiency disease caused by molecular defects in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. p67phox-CGD is an autosomal recessive CGD, which is caused by a defect in the cytosolic components of NADPH oxidase, p67phox, encoded by NCF2. We previously established a flow cytometric analysis for p67phox expression, which allows accurate assessment of residual protein expression in p67phox-CGD. We evaluated the correlation between oxidase function and p67phox expression, and assessed the relevancy to genotypes and clinical phenotypes in 11 patients with p67phox-CGD. Reactive oxygen species (ROS) production by granulocytes was evaluated using dihydrorhodamine-1,2,3 (DHR) assays. p67phox expression was evaluated in the monocyte population. DHR activity and p67phox expression were significantly correlated (r = 0.718, p < 0.0162). Additionally, DHR activity and p67phox expression were significantly higher in patients carrying one missense variant in combination with one nonsense or frameshift variant in the NCF2 gene than in patients with only null variants. The available clinical parameters of our patients (i.e., age at disease onset, number of infectious episodes, and each infection complication) were not linked with DHR activity or p67phox expression levels. In summary, our flow cytometric analysis revealed a significant correlation between residual ROS production and p67phox expression. More deleterious NCF2 genotypes were associated with lower levels of DHR activity and p67phox expression. DHR assays and protein expression analysis by using flow cytometry may be relevant strategies for predicting the genotypes of p67phox-CGD.

2.
J Am Chem Soc ; 144(41): 18744-18749, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36166343

RESUMEN

An organometallic nickel complex containing thieno[3,2-b]thiophene units was designed and synthesized. Composite films of the resulting nickel complex and polyvinylidene difluoride, which can be fabricated via a simple solution process under atmospheric conditions, exhibit remarkably high n-type conductivity (>200 S cm-1). Moreover, the thermoelectric power factor of the n-type composite film was proven to be air stable. A grazing-incidence wide-angle X-ray diffraction analysis indicated a significant impact of introducing the thieno[3,2-b]thiophene core into the backbone of the nickel complex on the orientation within the composite films.

3.
J Clin Immunol ; 42(7): 1434-1450, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35726044

RESUMEN

PURPOSE: Specific granule deficiency (SGD) is a rare inborn error of immunity resulting from loss-of-function variants in CEBPE gene (encoding for transcription factor C/EBPε). Although this genetic etiology has been known for over two decades, only a few patients with CEBPE variant-proven SGD (type I) have been reported. Herein, we describe two siblings with a novel homozygous CEBPE deletion who were noted to have profound neutropenia on initial evaluation. We aimed to evaluate the immunohematological consequences of this novel variant, including profound neutropenia. METHODS: Light scatter characteristics of granulocytes were examined on various automated hematology analyzers. Phagocyte immunophenotype, reactive oxygen species generation, and Toll-like receptor (TLR) signaling were assessed using flow cytometry. Relative expression of genes encoding various granule proteins was studied using RT-PCR. Western blot analysis and luciferase reporter assay were performed to explore variant C/EBPε expression and function. RESULTS: Severe infections occurred in both siblings. Analysis of granulocyte light scatter plots revealed automated hematology analyzers can provide anomalously low neutrophil counts due to abnormal neutrophil morphology. Neutrophils displayed absence/marked reduction of CD15/CD16 expression and overexpression (in a subset) of CD14/CD64. Three distinct populations of phagocytes with different oxidase activities were observed. Impaired shedding of CD62-ligand was noted on stimulation with TLR-4, TLR-2/6, and TLR-7/8 agonists. We demonstrated the variant C/EBPε to be functionally deficient. CONCLUSION: Homozygous c.655_665del variant in CEBPE causes SGD. Anomalous automated neutrophil counts may be reported in patients with SGD type I. Aberrant TLR signaling might be an additional pathogenetic mechanism underlying immunodeficiency in SGD type I.


Asunto(s)
Trastornos Leucocíticos , Neutropenia , Humanos , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Trastornos Leucocíticos/genética , Neutropenia/diagnóstico , Neutropenia/genética , Neutropenia/complicaciones , Neutrófilos
4.
Org Lett ; 23(20): 7921-7926, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34543032

RESUMEN

A domino-type multiple C-H functionalization of tetracene with molecular benzene is reported. Under the typical conditions of the Scholl reaction, a domino reaction occurs between tetracene and six molecules of benzene in one pot to furnish an aromatic compound with a curved π-system. This reaction sequence involves oxidative cross-dehydrogenative coupling/annulation and Friedel-Crafts-type reactions. Eight C-C bonds are formed via this intermolecular domino reaction without mediation by a metal or the assistance of a specific substituent.

5.
Org Lett ; 22(11): 4160-4163, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32383601

RESUMEN

A facile method for the direct cross-annulation of unfunctionalized tetracene is reported. The one-pot oxidative cross-dehydrogenative coupling (CDC) between tetracene and aromatic compounds, such as benzene or 2-methylthiophene, furnished annulated products with an extended π-network. Moreover, relative to the benzo-annulated tetracenes, thieno-annulated tetracenes exhibited notably improved photooxidative stability. This behavior stands in sharp contrast with that of tetracene and its derivatives, such as rubrene, which readily engage in photoinduced oxidation reactions.

6.
Biochem Biophys Res Commun ; 516(1): 293-299, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31256937

RESUMEN

CCAAT/enhancer binding protein epsilon (C/EBPε), a myeloid-specific transcription factor, plays an important role in granulopoiesis. A loss-of-function mutation in this protein can result in an abnormal development of neutrophils and eosinophils, known as neutrophil-specific granule deficiency (SGD). The transcriptional activity of C/EBPε is regulated by interactions with other transcription factors and/or post-translational modification, including acetylation. Previously, we reported a novel SGD patient who had a homozygous mutation for two amino acids, arginine (R247) and serine (S248), which were deleted in the basic leucine zipper domain of C/EBPε (ΔRS) and exhibited loss of transcriptional activity with aberrant protein-protein interactions. In the present study, we found that a single amino acid deletion of either R247 (ΔR) or S248 (ΔS) was sufficient for the loss of C/EBPε transcriptional activity, while an amino acid substitution at S248 to alanine in C/EBPε (SA) had comparable transcriptional activity with the wild-type C/EBPε (WT). Although acetylation at lysine residues (K121 and K198) is indispensable for C/EBPε transcriptional activity, an acetylation mimic form of ΔRS (ΔRS-K121/198Q) did not exhibit the transcriptional activity. Interestingly, we discovered that ΔRS, ΔR, ΔS, and ΔRS-K121/198Q interacted with histone deacetylase 1 (HDAC1), whereas WT and SA did not. Furthermore, the proteoglycan 2/eosinophil major basic protein induction activity of ΔRS, ΔR, and ΔS could be restored by the HDAC inhibitor, trichostatin A (TSA), and protein-protein interactions between ΔRS and Gata1 could also be recovered by TSA treatment. Taken together, our results show that TSA has the potential to restore the transcriptional activity of ΔRS, indicating that the inhibition of HDAC1 could be a molecularly targeted treatment for SGD with ΔRS.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Histona Desacetilasa 1/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/farmacología , Lactoferrina/deficiencia , Trastornos Leucocíticos/metabolismo , Mapas de Interacción de Proteínas/efectos de los fármacos , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Proteínas Potenciadoras de Unión a CCAAT/genética , Factor de Transcripción GATA1/metabolismo , Células HEK293 , Humanos , Lactoferrina/genética , Lactoferrina/metabolismo , Trastornos Leucocíticos/tratamiento farmacológico , Trastornos Leucocíticos/genética , Ratones , Células 3T3 NIH , Eliminación de Secuencia
8.
Cancer Sci ; 106(8): 965-71, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25990049

RESUMEN

Hypersensitivity to mosquito bites (HMB) is a cutaneous disorder belonging to the group of Epstein-Barr virus (EBV)-associated T/natural killer (NK)-cell lymphoproliferative diseases, and is primarily mediated by EBV-infected NK cells. It is characterized by intense local skin reactions accompanied by general symptoms after mosquito bites, and infiltration of EBV-infected NK cells into the bite sites. However, the mechanisms underlying these reactions have not been fully examined. We recently described the activation of circulating basophils by mosquito extracts in vitro in a patient with HMB. To further investigate this finding, we studied four additional patients with HMB. All patients showed typical clinical features of HMB after mosquito bites and they had NK lymphocytosis and high peripheral blood EBV DNA loads. We found evidence of EBV infection in NK cells through in situ hybridization that detected EBV-encoded small RNA-1, and flow cytometry showed HLA-DR expression on almost all NK cells. Basophil activation tests with the extracts of epidemic mosquitoes Culex pipiens pallens and Aedes albopictus showed positive responses to one or both extracts in all samples from patients with HMB, suggesting the presence of mosquito antigen-specific IgE and its binding to basophils. In particular, the extract of Aedes albopictus was able to activate basophils in all available patient samples. These results indicate that basophils and/or mast cells activated by mosquito bites may be involved in initiation and development of severe skin reactions to mosquito bites in HMB.


Asunto(s)
Basófilos/inmunología , Culicidae/inmunología , Hipersensibilidad/inmunología , Mordeduras y Picaduras de Insectos/inmunología , Animales , Prueba de Desgranulación de los Basófilos , Niño , Preescolar , Femenino , Citometría de Flujo , Humanos , Hibridación in Situ , Masculino
9.
J Immunol ; 195(1): 80-6, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26019275

RESUMEN

Neutrophil-specific granule deficiency (SGD) is a rare autosomal recessive primary immunodeficiency characterized by neutrophil dysfunction, bilobed neutrophil nuclei and lack of neutrophil-specific granules. Defects in a myeloid-specific transcription factor, CCAAT/enhancer binding protein-ε (C/EBPε), have been identified in two cases in which homozygous frameshift mutations led to loss of the leucine zipper domain. In this study, we report a 55-y-old woman affected with SGD caused by a novel homozygous 2-aa deletion (ΔRS) in the leucine zipper domain of the C/EBPε gene. The patient showed characteristic neutrophil abnormalities and recurrent skin infections; however, there was no history of deep organ infections. Biochemical analysis revealed that, in contrast to the two frameshift mutations, the ΔRS mutant maintained normal cellular localization, DNA-binding activity, and dimerization, and all three mutants exhibited marked reduction in transcriptional activity. The ΔRS mutant was defective in its association with Gata1 and PU.1, as well as aberrant cooperative transcriptional activation of eosinophil major basic protein. Thus, the ΔRS likely impairs protein-protein interaction with other transcription factors, resulting in a loss of transcriptional activation. These results further support the importance of the leucine zipper domain of C/EBPε for its essential function, and indicate that multiple molecular mechanisms lead to SGD.


Asunto(s)
Secuencia de Bases , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/inmunología , Lactoferrina/deficiencia , Trastornos Leucocíticos/genética , Neutrófilos/inmunología , Eliminación de Secuencia , Adulto , Gránulos Citoplasmáticos/inmunología , Gránulos Citoplasmáticos/patología , Proteína Mayor Básica del Eosinófilo/genética , Proteína Mayor Básica del Eosinófilo/inmunología , Femenino , Factor de Transcripción GATA1/genética , Factor de Transcripción GATA1/inmunología , Regulación de la Expresión Génica , Homocigoto , Humanos , Lactoferrina/genética , Lactoferrina/inmunología , Trastornos Leucocíticos/inmunología , Trastornos Leucocíticos/patología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Neutrófilos/patología , Unión Proteica , Estructura Terciaria de Proteína , Proteoglicanos/genética , Proteoglicanos/inmunología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/inmunología , Transducción de Señal , Transactivadores/genética , Transactivadores/inmunología , Transcripción Genética
12.
J Nanosci Nanotechnol ; 14(4): 3193-201, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24734754

RESUMEN

(Apo)ferritins are cage-shaped proteins which have recently received a great deal of attention because the inner cavity of the protein shell can be used as a size-restricted reaction field for the synthesis of nanomaterials. The biomineralization behavior and inorganic nanoparticle (NP) synthesis mechanism of (apo)ferritin in solution systems have been studied but the mineralization behavior of (apo)ferritin on the substrates has not yet been well studied. Here, we conducted quantitative and kinetic analyses of the mineralization behavior of immobilized (apo)ferritin on a polyelectrolyte multilayer (PEM) using quartz crystal microbalance (QCM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. We demonstrated that the (apo)ferritin immobilized on a substrate synthesizes a ferrihydrite core within the confines of the protein cage; similar to a solution dispersed system. In addition, we applied a ferritin/apoferritin blended monolayer to the study of iron mineralization and revealed that biomineralization in this system is spatially selective. It is important to understand the mineralization mechanisms for the synthesis of other functional NPs as this approach has potential for a broad range of magnetic, catalytic, and biomedical sensing applications.


Asunto(s)
Ferritinas/química , Proteínas Inmovilizadas/química , Hierro/química , Minerales/química , Adsorción , Animales , Apoproteínas/química , Compuestos Férricos/química , Caballos , Microscopía Electrónica de Rastreo , Espectroscopía de Fotoelectrones , Tecnicas de Microbalanza del Cristal de Cuarzo
13.
Pediatr Nephrol ; 29(5): 915-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24240509

RESUMEN

BACKGROUND: Nephrotic syndrome (NS) is characterized by water and sodium retention, which leads to edema. The non-osmotic stimulation of arginine vasopressin release from the pituitary gland has been implicated as one of the important factors in abnormal water retention in patients with NS. CASE-DIAGNOSIS/TREATMENT: We present the initial description of a patient with massive edema caused by refractory nephrotic syndrome, which was effectively treated with tolvaptan, a selective oral vasopressin V2 receptor antagonist. CONCLUSIONS: Tolvaptan is effective for the treatment of massive edema caused by NS. Larger studies are needed in the future to fully assess the value and safety of tolvaptan use for this condition.


Asunto(s)
Antagonistas de los Receptores de Hormonas Antidiuréticas/uso terapéutico , Benzazepinas/uso terapéutico , Edema/tratamiento farmacológico , Edema/etiología , Síndrome Nefrótico/complicaciones , Antiinflamatorios/uso terapéutico , Niño , Femenino , Humanos , Prednisolona/uso terapéutico , Diálisis Renal , Tolvaptán , Urodinámica
14.
Pediatr Blood Cancer ; 60(7): E46-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23382108

RESUMEN

Primary Epstein-Barr virus (EBV) infection causes infectious mononucleosis and hemophagocytic lymphohistiocytosis (HLH) in children, where EBV infects B and CD8(+) T cells, respectively. We measured pro-inflammatory and anti-inflammatory cytokines in both diseases. Significantly higher concentrations of various mediators, including interferon-γ, neopterin, interleukin (IL)-6, IL-10, IL-18, and heme oxygenase-1, were observed in EBV-HLH. Because of their similarity to the profile of familial HLH, this profile was likely a consequence of HLH, but not ectopic infection. TNF-α levels were elevated in both diseases. Elevation of those mediators may contribute to the disease pathogenesis of EBV-HLH by activating and inhibiting host immune responses.


Asunto(s)
Citocinas/sangre , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino
15.
J Clin Immunol ; 33(4): 857-64, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23306776

RESUMEN

Chronic granulomatous disease (CGD) is caused by defects of NADPH oxidase. The diagnosis of CGD can be made by analysis of NADPH oxidase activity, however, identification of the CGD subgroups is required before performing mutation analysis. The membrane-bound subunits, gp91phox and p22phox, can be quickly analyzed by flow cytometry, unlike the cytosolic components, p47phox and p67phox. We evaluated the feasibility of flow cytometric detection of p47phox and p67phox with specific monoclonal antibodies in two patients with p47phox deficiency and 7 patients with p67phox deficiency. Consistent with previous observations, p47phox and p67phox were expressed in phagocytes and B cells, but not in T or natural killer cells, from normal controls. In contrast, patients with p47phox and p67phox deficiency showed markedly reduced levels of p47phox and p67phox, respectively. These techniques will be useful to rapidly assess the expression of the cytosolic components, p47phox and p67phox, and represents important secondary screening tests for CGD.


Asunto(s)
Linfocitos B/inmunología , Citosol/metabolismo , Citometría de Flujo/métodos , Enfermedad Granulomatosa Crónica/diagnóstico , NADPH Oxidasas/metabolismo , Fagocitos/inmunología , Fosfoproteínas/análisis , Adolescente , Adulto , Separación Celular , Células Cultivadas , Niño , Preescolar , Análisis Mutacional de ADN , Estudios de Factibilidad , Femenino , Enfermedad Granulomatosa Crónica/inmunología , Humanos , Lactante , Recién Nacido , Masculino , Tamizaje Masivo , Mutación/genética , NADPH Oxidasas/análisis , NADPH Oxidasas/genética , Adulto Joven
16.
J Colloid Interface Sci ; 378(1): 44-50, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22564766

RESUMEN

In this study, we quantitatively analyzed the electrostatic blend adsorption of ferritin and apoferritin onto the surface of the precursor films by using a quartz crystal microbalance (QCM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The precursor films were successively prepared by the alternate adsorption of poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrenesulfonate) (PSS) in the presence of 150 mM NaCl concentration onto the QCM substrate. We observed a monolayer adsorption of both ferritin and apoferritin by means of electrostatic interaction onto the outermost PDDA surface at pH 10.0. Under this condition, the composition of ferritin and apoferritin within the monolayer is linearly dependent on their ratios in the blended solution, thus showed an ideal blend adsorption behavior. The perfectly identical structure of ferritin and apoferritin should be contributed to this ideal blend adsorption behavior. We also studied the effects of total concentrations of their solution on ferritin and apoferritin blend adsorption. This study on the blend adsorption of ferritin and apoferritin by electrostatic interaction will be applied to the fabrication of multi-components homogeneous NP array because apoferritin can accommodate a variety of nanometer size inorganic materials within their interior spaces.


Asunto(s)
Apoferritinas/química , Nanoestructuras/química , Polietilenos/química , Polímeros/química , Compuestos de Amonio Cuaternario/química , Ácidos Sulfónicos/química , Animales , Caballos , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Cloruro de Sodio/química , Electricidad Estática
17.
Mol Pharm ; 9(4): 922-9, 2012 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-22352425

RESUMEN

A carboxyl group-terminated polyamidoamine dendrimer (generation: 3.0) bearing arbutin, which is a substrate of Na⁺/glucose cotransporter 1 (SGLT1), via a nonbiodegradable ω-amino triethylene glycol linker (PAMAM-ARB), inhibits SGLT1-mediated D-glucose uptake, as does phloridzin, which is a typical SGLT1 inhibitor. Here, since our previous research revealed that the activity of arbutin was dramatically improved through conjugation with the dendrimer, we examined the involvement of functional groups on the dendrimer surface in inhibition of SGLT1-mediated D-glucose uptake. PAMAM-ARB, with a 6.25% arbutin content, inhibited in vitro D-glucose uptake most strongly; the inhibitory effect decreased as the arbutin content increased. In vitro experiments using arbutin-free original dendrimers indicated that dendrimer-derived carboxyl groups actively participated in SGLT1 inhibition. However, the inhibitory effect was much less than that of PAMAM-ARB and was equal to that of glucose moiety-free PAMAM-ARB. Data supported that the glucose moiety of arbutin was essential for the high activity of PAMAM-ARB in SGLT1 inhibition. Analysis of the balance of each domain further suggested that carboxyl groups anchored PAMAM-ARB to SGLT1, and the subsequent binding of arbutin-derived glucose moieties to the target sites on SGLT1 resulted in strong inhibition of SGLT1-mediated D-glucose uptake.


Asunto(s)
Arbutina/química , Dendrímeros/química , Dendrímeros/farmacología , Glucosa/metabolismo , Poliaminas/química , Transportador 1 de Sodio-Glucosa/metabolismo , Transporte Biológico/efectos de los fármacos , Dendrímeros/síntesis química , Humanos
18.
J Oleo Sci ; 59(7): 369-73, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20513970

RESUMEN

Monoazacryptand [20.18.18] (1), monoaza-15-crown-5 (2a), and monoaza-18-crown-6 (2b) with a partially fluorinated sidearm were newly prepared and their transport abilities were estimated in a supported liquid membrane containing a mixture of 2- (perfluorohexyl) ethyl alcohol and 2- (perfluorooctyl) ethyl alcohol. In competitive passive transport of K+, Na+, and Li+ under neutral conditions, the K+ selectivity increased in the order: ionophore 2a

Asunto(s)
Éteres Corona , Membranas Artificiales , Metales Alcalinos , Halogenación , Concentración de Iones de Hidrógeno , Ionóforos , Potasio
19.
Org Biomol Chem ; 8(10): 2408-13, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20448899

RESUMEN

A ditopic macrocycle with a bisamide and a half dibenzo-crown ether component has been newly synthesized and its complexation behavior toward neutral phenanthroline derivatives is reported. The macrocycle can bind phenanthroline derivatives very strongly by hydrogen bonding and pi-electron interaction, yielding pseudorotaxane structures. The inclusion complexes show a pH controllable reversible threading-dethreading molecular switching system.

20.
J Colloid Interface Sci ; 338(1): 222-8, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19604513

RESUMEN

Stable 'Pickering-type' emulsions were prepared using ferritin, a spherical protein, as a bionano-particulate emulsifier and n-dodecane, toluene, castor oil, olive oil or vegetable oil as an oil phase, in the absence of any surfactant molecules. All the emulsions prepared were of the oil-in-water type and an increase of ferritin concentration decreased the volume average droplet diameters. Transmission electron microscopy studies of the ferritin residues remaining after evaporation of oil and water from the emulsion revealed a broken capsule morphology, which is strong evidence for the attachment of ferritin at the oil-water interface thereby stabilizing the emulsion. The emulsion droplets could be elongated and made to pass through a glass capillary.


Asunto(s)
Emulsionantes/química , Ferritinas/química , Nanopartículas/química , Microscopía Electrónica de Transmisión
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