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1.
J Allergy Clin Immunol ; 146(4): 901-911, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32278790

RESUMEN

BACKGROUND: An increasing number of NFKB1 variants are being identified in patients with heterogeneous immunologic phenotypes. OBJECTIVE: To characterize the clinical and cellular phenotype as well as the management of patients with heterozygous NFKB1 mutations. METHODS: In a worldwide collaborative effort, we evaluated 231 individuals harboring 105 distinct heterozygous NFKB1 variants. To provide evidence for pathogenicity, each variant was assessed in silico; in addition, 32 variants were assessed by functional in vitro testing of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB) signaling. RESULTS: We classified 56 of the 105 distinct NFKB1 variants in 157 individuals from 68 unrelated families as pathogenic. Incomplete clinical penetrance (70%) and age-dependent severity of NFKB1-related phenotypes were observed. The phenotype included hypogammaglobulinemia (88.9%), reduced switched memory B cells (60.3%), and respiratory (83%) and gastrointestinal (28.6%) infections, thus characterizing the disorder as primary immunodeficiency. However, the high frequency of autoimmunity (57.4%), lymphoproliferation (52.4%), noninfectious enteropathy (23.1%), opportunistic infections (15.7%), autoinflammation (29.6%), and malignancy (16.8%) identified NF-κB1-related disease as an inborn error of immunity with immune dysregulation, rather than a mere primary immunodeficiency. Current treatment includes immunoglobulin replacement and immunosuppressive agents. CONCLUSIONS: We present a comprehensive clinical overview of the NF-κB1-related phenotype, which includes immunodeficiency, autoimmunity, autoinflammation, and cancer. Because of its multisystem involvement, clinicians from each and every medical discipline need to be made aware of this autosomal-dominant disease. Hematopoietic stem cell transplantation and NF-κB1 pathway-targeted therapeutic strategies should be considered in the future.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Heterocigoto , Mutación , Subunidad p50 de NF-kappa B/genética , Fenotipo , Adulto , Anciano , Autoinmunidad/genética , Variación Biológica Poblacional , Biomarcadores , Manejo de la Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Estudios de Asociación Genética/métodos , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Tomografía Computarizada por Rayos X
2.
Clin Immunol ; 210: 108269, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31683054

RESUMEN

Genetic studies have led to identification of an increasing number of monogenic primary immunodeficiency disorders. Monoallelic pathogenic gain-of-function (GOF) variants in NFKBIA, the gene encoding IκBα, result in an immunodeficiency disorder, typically accompanied by anhidrotic ectodermal dysplasia (EDA). So far, 14 patients with immunodeficiency due to NFKBIA GOF mutations have been reported. In this study we report three patients from the same family with immunodeficiency, presenting with recurrent respiratory tract infections, bronchiectasis and viral skin conditions due to a novel pathogenic NFKBIA variant (c.106 T > G, p.Ser36Ala), which results in reduced IκBα degradation. Immunological investigations revealed inadequate antibody responses against vaccine antigens, despite hypergammaglobulinemia. Interestingly, none of the studied patients displayed features of EDA. Therefore, missense NFKBIA variants substituting serine 36 of IκBα, differ from the rest of pathogenic GOF NFKBIA variants in that they cause combined immunodeficiency, even in the absence of EDA.


Asunto(s)
Mutación con Ganancia de Función/genética , Síndromes de Inmunodeficiencia/diagnóstico , Leucocitos Mononucleares/inmunología , Meningitis Bacterianas/diagnóstico , Inhibidor NF-kappaB alfa/genética , Neisseria meningitidis/fisiología , Papillomaviridae/fisiología , Infecciones por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/fisiología , Virosis/inmunología , Adulto , Artritis Juvenil , Azitromicina/uso terapéutico , Bronquiectasia , Proliferación Celular , Células Cultivadas , Niño , Displasia Ectodérmica , Gentamicinas/uso terapéutico , Humanos , Síndromes de Inmunodeficiencia/genética , Masculino , Meningitis Bacterianas/tratamiento farmacológico , Linaje , Infecciones por Pseudomonas/tratamiento farmacológico , Virosis/diagnóstico , Verrugas , Adulto Joven
3.
Nephrol Dial Transplant ; 33(6): 1065-1072, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29444269

RESUMEN

Background: We analysed in a carefully phenotyped cohort of paediatric patients the association of serum angiotensin II type 1 receptor antibodies (AT1R-Ab) with specific histological lesions and with graft function and survival in conjunction with overall and complement-binding donor-specific human leucocyte antigen donor-specific antibodies (HLA-DSA). Methods: Sera of 62 patients at the time of renal graft biopsy for clinical indication >1 year post-transplant were assessed for AT1R-Ab by enzyme-linked immunosorbent assay (ELISA) and for DSA and C1q-fixing DSA by single-antigen bead technology. Results: Serum AT1R-Ab concentration was significantly higher in antibody-mediated rejection (ABMR) than in T-cell-mediated rejection or control. By receiver operating characteristic (ROC) curve analysis, the optimal AT1R-Ab cut-off value discriminating between patients with features of ABMR and those without was 9.5 U/mL. A total of 6 of 28 patients (21.4%) with ABMR were only positive for AT1R-Ab. Patients with AT1R-Ab and HLA-DSA double positivity had a significantly higher vascular micro-inflammation score than DSA-negative patients. The 5-year graft survival was only 59% in the AT1R-Ab-positive group compared with 87% in the AT1R-Ab-negative group. Patients with AT1R-Ab and HLA-DSA double positivity tended to have a more rapid decline of estimated glomerular filtration rate (eGFR) than patients who were only positive for AT1R-Ab or HLA-DSA. In a multivariate Cox regression model of non-invasive factors, C1q-positive HLA-DSA, eGFR and AT1R-Ab positivity were significantly associated with accelerated graft function decline. Conclusions: Serum AT1R-Ab positivity in the context of an indication biopsy >1 year post-transplant is associated with the histopathology of ABMR and is an independent non-invasive risk factor for adverse graft outcome.


Asunto(s)
Anticuerpos/efectos adversos , Rechazo de Injerto/mortalidad , Supervivencia de Injerto , Antígenos HLA/inmunología , Trasplante de Riñón/efectos adversos , Receptor de Angiotensina Tipo 1/inmunología , Receptores de Trasplantes/estadística & datos numéricos , Adolescente , Adulto , Anticuerpos/inmunología , Niño , Femenino , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Rechazo de Injerto/patología , Humanos , Masculino , Receptor de Angiotensina Tipo 1/sangre , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Donantes de Tejidos
4.
Clin Immunol ; 179: 1-7, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28216420

RESUMEN

Here we describe novel mutations in recombination activation gene 1 (RAG1) in a compound heterozygous male patient with combined T and B cell immunodeficiency (CID). Clinical manifestations besides antibody deficiency included airway infections, granulomatosis and autoimmune features. He died at the age of 37 due to PML caused by JC virus infection. By targeted next-generation sequencing we detected post mortem in this patient three mutations in RAG1. One allele harbored two novel mutations (c.1123C>G, p.H375D and c.1430delC, p.F478Sfs*14), namely a missense variant and a frameshift deletion, of which the latter leads to a truncated RAG1 protein. The other allele revealed a previously described missense mutation (c.1420C>T, p.R474C, rs199474678). Functional analysis of the p.R474C variant in an in vitro V(D)J recombination assay exhibited reduced recombination activity compared to a wild-type control. Our findings suggest that mutations in RAG1, specifically the p.R474C variant, can be associated with relatively mild clinical symptoms or delayed occurrence of T cell and B cell deficiencies but may predispose to PML.


Asunto(s)
Proteínas de Homeodominio/genética , Síndromes de Inmunodeficiencia/genética , Leucoencefalopatía Multifocal Progresiva/genética , Adulto , Linfocitos B/inmunología , Biopsia , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Proliferación Celular , Humanos , Inmunoglobulinas/sangre , Síndromes de Inmunodeficiencia/sangre , Síndromes de Inmunodeficiencia/diagnóstico por imagen , Síndromes de Inmunodeficiencia/inmunología , Leucoencefalopatía Multifocal Progresiva/sangre , Leucoencefalopatía Multifocal Progresiva/diagnóstico por imagen , Leucoencefalopatía Multifocal Progresiva/inmunología , Recuento de Linfocitos , Imagen por Resonancia Magnética , Masculino , Mutación , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Recombinación V(D)J
5.
J Public Health (Oxf) ; 38(1): 84-91, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25665877

RESUMEN

BACKGROUND: The phenomenon of waterpipe smoking (WPS) among adolescents has become eminent, and it is especially prevalent in Lebanon. Unlike cigarette smoking, WPS is parentally and socially acceptable. This study aims at examining the association between intention to smoke waterpipe in the next 6 months, and knowledge, attitudes and parental and social influences. METHODS: This is a secondary data analysis from a national survey in 2007 on 1028 households. This study addresses 258 non-smoking adolescents and their parents. Consent was sought and the study was approved by the Institutional Review Board at the American University of Beirut. Face-to-face interviews were conducted. Descriptive analysis, crude and adjusted odds ratios (ORs) were generated. RESULTS: At the bivariate level, late adolescence, mothers without university education, prior adolescents' WPS experiences, best friends' and parents' WPS habits and adolescents' and parents' lower attitude scores were associated with smoking intention. In the adjusted model, adolescents' beliefs about positive effects, best friends' similar habits and prior smoking remained significant (respective ORs [95% confidence interval ]: 1.81 [1.33-2.45], 2.51 [1.24-5.10], 4.91 [2.35-10.36]). Parents' perceived attitude against smoking was protective (OR: 0.57 [0.39-0.83]). CONCLUSIONS: Adolescents' intention to smoke is highly influenced by parents' permissive attitudes and peer pressure. Interventions targeting these two groups and limiting access to smoking by adolescents should be instigated.


Asunto(s)
Fumar/epidemiología , Adolescente , Factores de Edad , Escolaridad , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Intención , Entrevistas como Asunto , Líbano , Masculino , Padres/psicología , Fumar/psicología , Encuestas y Cuestionarios
6.
J Ultrasound Med ; 35(7): 1593-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27335443

RESUMEN

Six patients with 7 lesions that were histologically confirmed as primary testicular lymphoma were preoperatively investigated with a standardized sonographic protocol including contrast-enhanced sonography. Duplex and contrast-enhanced sonography showed marked hypervascularization in all 7 lesions. On contrast-enhanced sonography, the filling time of lymphomatous lesions was significantly shorter than the filling time of a size-matched sample of 10 patients with seminomas (P < .0001). The sonographic hallmarks of testicular lymphoma in our case series were as follows: (1) sharply demarcated homogeneous hypoechoic testicular lesions with marked hypervascularization; (2) a rapid (<7 seconds) filling time of contrast bubbles; and (3) a straight and parallel course of intralesional vessels on contrast-enhanced sonography.


Asunto(s)
Medios de Contraste/farmacocinética , Aumento de la Imagen/métodos , Linfoma/diagnóstico por imagen , Fosfolípidos/farmacocinética , Hexafluoruro de Azufre/farmacocinética , Neoplasias Testiculares/diagnóstico por imagen , Ultrasonografía/métodos , Anciano , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Testiculares/irrigación sanguínea , Testículo/irrigación sanguínea , Testículo/diagnóstico por imagen , Tiempo
7.
BMC Public Health ; 15: 578, 2015 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-26093501

RESUMEN

BACKGROUND: Seasonal influenza is one of the most significant infectious diseases in Germany; epidemic outbreaks occur every winter and cause substantial morbidity and mortality. However, published data from Germany on the current economic burden of influenza and the costs per episode are lacking. METHODS: A retrospective database analysis was conducted using a longitudinal electronic medical records database (IMS Disease Analyzer). Patients with influenza, diagnosed by German office-based physicians using ICD-10 J09-11 (International Classification of Diseases, 10(th) revision), who were observable in the database from 12 months before the index (diagnosis) date until 1 month afterwards, were included. The selection window, defined to cover two influenza seasons, was May 2010 to April 2012. Direct and indirect costs were evaluated from payer, patient and societal perspectives. Published unit costs and tariffs from Germany (2012) were used for the analysis. RESULTS: A total of 21,039 influenza-attributable episodes in 17,836 adults, managed by primary care physicians (PCP) and 7,107 episodes in 6,288 children, managed by pediatricians, were eligible for analysis. The mean (±Standard Deviation (SD)) age of the adults with at least one episode was 46 (±18) years and 7 (±4) years in the children. The presence of clinical risk factors was documented for 39% episodes in adults and 24% episodes in children, with the most common being cardiovascular diseases in adults (29%) and chronic respiratory diseases in children (23%). Complications and severe symptoms accompanied the influenza-attributable episode (adults: 37%, children: 54%), bronchitis (adults: 16%, children: 19%) and acute upper respiratory infection (adults: 15%, children: 21%) being the most frequent. From a societal perspective, the total average mean cost (±SD) per episode was €514 (±609) in adults, where work days lost were the main cost driver (82%), and €105 (±224) in children. Complications and severe symptoms increased the cost per episode versus episodes without by 1.7 times in adults (€684 (±713) vs. €413 (±510)) and nearly 3 times in children (€149 (±278) vs. €55 (±116)). CONCLUSIONS: Based on a large patient sample derived from representative PCP and pediatricians panels, our results demonstrate that seasonal influenza is associated with substantial clinical and economic burden in Germany.


Asunto(s)
Bases de Datos Factuales/estadística & datos numéricos , Gastos en Salud/estadística & datos numéricos , Gripe Humana/economía , Atención Primaria de Salud/estadística & datos numéricos , Absentismo , Adolescente , Adulto , Niño , Preescolar , Costo de Enfermedad , Femenino , Alemania/epidemiología , Servicios de Salud/economía , Servicios de Salud/estadística & datos numéricos , Humanos , Gripe Humana/complicaciones , Clasificación Internacional de Enfermedades , Masculino , Persona de Mediana Edad , Pediatría/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo
10.
Chembiochem ; 13(7): 993-8, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22504937

RESUMEN

Diaminoterephthalates with a maleimide moiety were synthesized and used as fluorescence dyes for sensing thiols. Whereas these "NiWa Blue" dyes showed no emission, the conjugate addition of a thiol to the maleimide group turned on a fluorescence at about 400 nm when irradiating the dye at 338 nm. The neuronal-calcium sensor protein recoverin possesses a single cysteine residue at position 39, which reacts with NiWa Blue, and is therefore labeled by a fluorophore with an emission at about 440 nm. In the absence of Ca(2+), irradiation at 280 nm of a tryptophan residue in close proximity to Cys-bound NiWa Blue lead to strong FRET, which was detected by emission of the dye at 440 nm. In the presence of Ca(2+), the protein holds a conformation with distal Trp and Cys residues, thus FRET of irradiated Trp to Cys-bound NiWa Blue was significantly weakened.


Asunto(s)
Colorantes Fluorescentes/química , Ácidos Ftálicos/química , Recoverina/química , Espectrometría de Fluorescencia/métodos , Compuestos de Sulfhidrilo/química , Cromatografía Líquida de Alta Presión/métodos , Química Clic , Conformación Proteica , Recoverina/análisis , Compuestos de Sulfhidrilo/análisis
11.
J Dtsch Dermatol Ges ; 7(10): 896-8, 2009 Oct.
Artículo en Inglés, Alemán | MEDLINE | ID: mdl-19453384

RESUMEN

A 52-year-old geriatric nurse presented with recurrent eczema localized in uncovered skin areas. Patch testing produced an eczematous skin reaction with type IV sensitization totetrazepam. A relapse of contact dermatitis was successfully prevented by using occupational skin protection measures and organizational measures.Our case indicates that a sensitization to drugs should be considered when allergic contact dermatitisis suspected in nursing personnel.


Asunto(s)
Benzodiazepinas/efectos adversos , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/etiología , Dermatitis Profesional/diagnóstico , Dermatitis Profesional/etiología , Enfermería Geriátrica , Enfermeras y Enfermeros , Dermatitis Alérgica por Contacto/prevención & control , Dermatitis Profesional/prevención & control , Femenino , Humanos , Persona de Mediana Edad
12.
Front Immunol ; 10: 2618, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31803180

RESUMEN

Adult-onset primary immunodeficiency is characterized by recurrent infections, hypogammaglobulinemia, and poor antibody response to vaccines. In this study, we have analyzed targeted gene panel sequencing results of 270 patients diagnosed with antibody deficiency and identified five disease-associated variants in NFKB1 in five unrelated families. We detected two single base pair deletions and two single base pair insertions, causing severe protein truncations, and one missense mutation. Immunoblotting, lymphocyte stimulation, immunophenotyping, and ectopic expression assays demonstrated the functional relevance of NFKB1 mutations. Besides antibody deficiency, clinical manifestations included infections, autoimmune features, lymphoproliferation, lymphoma, Addison's disease, type 2 diabetes and asthma. Although partial clinical penetrance was observed in almost all pedigrees, all carriers presented a deficiency in certain serum immunoglobulins and the majority showed a lack of memory B cells (CD19+CD27+). Among all tested genes, NFKB1 alterations were the most common monoallelic cause of antibody deficiency in our cohort.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Subunidad p50 de NF-kappa B/genética , Enfermedades de Inmunodeficiencia Primaria/genética , Adolescente , Adulto , Edad de Inicio , Alelos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Subunidad p50 de NF-kappa B/inmunología , Linaje , Enfermedades de Inmunodeficiencia Primaria/inmunología , Adulto Joven
13.
Sci Total Environ ; 573: 1370-1379, 2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27436779

RESUMEN

The implementation of quality control procedures in analytical laboratories around the world has become essential in order to ensure the quality and safety of food. This article describes the procedure adopted by the Brazilian government in order to achieve this goal, specifically in the area of analysis of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The validation of a multiresidue method, the calculation of measurement uncertainty, and the quality control procedure adopted in the determination of these compounds in beef cattle fat were performed as set out in national legislation (Brasil, 2011), which is aligned with international guidelines. Evaluation was made of selectivity, linearity, precision (repeatability and reproducibility), accuracy, and limits of detection and quantification. Stability studies were also undertaken. The technique was extended to three other matrices (poultry, horse, and pig adipose tissues), with evaluation of matrix effects, selectivity, linearity, and accuracy. The analyses were performed by gas chromatography with electron capture detection (GC-ECD) and mass spectrometric detection (GC-MS). In recent years, analyses conducted under the National Plan for Control of Residues and Contaminants (PNCRC) have shown no exceedances of the maximum permitted residue levels (MRLs) of pesticides and PCBs in these tissues, as observed in other countries that carry out effective monitoring of these contaminants.


Asunto(s)
Tejido Adiposo/química , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Contaminación de Alimentos/análisis , Carne/análisis , Compuestos Orgánicos/análisis , Animales , Brasil , Bovinos , Caballos , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Aves de Corral , Sus scrofa
14.
Ultrasound Med Biol ; 42(8): 1807-15, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27181687

RESUMEN

This study investigates the usefulness of contrast-enhanced ultrasound (CEUS) and real-time elastography (RTE) for the characterization of testicular masses by comparing pre-operative ultrasound findings with post-operative histology. Sixty-seven patients with 68 sonographically detected testicular masses underwent B-mode, color-coded Doppler sonography (CCDS), CEUS and RTE according to defined criteria. For RTE, elasticity score (ES), difference of elasticity score (D-ES), strain ratio (SR) and size quotient (Qsize) were evaluated. Histopathologically, 54/68 testicular lesions were neoplastic (47 malignant, 7 benign). Descriptive statistics revealed the following results (neoplastic vs. non-neoplastic) for sensitivity, specificity, positive predictive value, negative predictive value and accuracy, respectively: B-mode, 100%, 43%, 87%, 100%, 88%; CCDS 81%, 86%, 96%, 55%, 82%; CEUS 93%, 85%, 96%, 73%, 91%; ES 98%, 25%, 85%, 75%, 85%; D-ES 98%, 50%, 90%, 83%, 89%; SR 90%, 45%, 86%, 56%, 81%; and Qsize 57%, 83%, 94%, 28%, 61%. B-mode with CCDS remains the standard for assessing testicular masses. In characterization of testicular lesions, CEUS clearly outperformed all other modalities. Our study does not support the routine use of RTE in testicular ultrasonography because of its low specificity.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Fosfolípidos , Hexafluoruro de Azufre , Neoplasias Testiculares/diagnóstico por imagen , Ultrasonografía/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Testículo/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Adulto Joven
15.
Mol Endocrinol ; 16(5): 961-76, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11981032

RESUMEN

Several cell lines, including ROS17/2.8 rat osteosarcoma (ROS) cells, contain functional VDRs and RXRs but are resistant to the antiproliferative effects of calcitriol and retinoids. We explored the role of receptor degradation in this hormone resistance. Results of transactivation assays indicated that ROS cells contain insufficient amounts of RXR to activate a DR-1 reporter, and Western blot analyses of cell extracts showed that the degradation of RXR is accelerated and produces an aberrant 45-kDa RXR. We stably expressed functional fluorescent chimeras of VDR and RXR [green fluorescent protein (GFP)-VDR; yellow fluorescent protein (YFP)-RXR] to evaluate degradation mechanisms and the impact of excess receptor expression on antiproliferative effects. Microscopy showed a diminished expression of YFP-RXR in ROS cells compared with the expression in CV-1 cells. Treatment with inhibitors of proteasomal degradation (lactacystin and MG132) selectively enhanced GFP-VDR and YFP-RXR expression and also increased the endogenous levels of VDR and RXR. Expression of GFP-VDR had no effect on the sensitivity of ROS cells to calcitriol. Increases of RXR levels by YFP-RXR expression, drug treatments, or the combination of the two, however, restored the growth-inhibitory effects of calcitriol and 9-cis-RA and restored p21 induction by calcitriol. These studies revealed that an accelerated and aberrant RXR degradation could cause resistance to the antiproliferative effects of calcitriol and retinoids in ROS cells.


Asunto(s)
Calcitriol/farmacología , División Celular/efectos de los fármacos , Osteosarcoma/patología , Receptores de Ácido Retinoico/metabolismo , Factores de Transcripción/metabolismo , Animales , Proteínas Bacterianas/genética , Western Blotting , Cisteína Endopeptidasas/metabolismo , Resistencia a Medicamentos , Expresión Génica , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Complejos Multienzimáticos/antagonistas & inhibidores , Complejos Multienzimáticos/metabolismo , Complejo de la Endopetidasa Proteasomal , Ratas , Receptores de Calcitriol/genética , Proteínas Recombinantes de Fusión , Receptores X Retinoide , Retinoides/farmacología , Transcripción Genética , Células Tumorales Cultivadas
16.
Int J Oncol ; 20(1): 195-200, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11743664

RESUMEN

Tributyrin (glyceryl tributyrate, TB) is known to induce malignant cells to differentiate followed by arrest of cell growth and death via apoptosis. We investigated the effects of TB on the distribution of cell cycle phases, differentiation as measured by alkaline phosphatase activity (ALP), and apoptosis of LS 174T colon cancer cells expressed by morphological changes, externalization of phosphatidylserine and stimulation of various caspases. TB (0.6 mM) reduced the proliferation by a 5-fold decrease of tumor cells in the S-phase and 1.3-fold increase in the G2/M-phase of cell cycle after 24 h of incubation. The ALP activity was enhanced in a dose-dependent manner up to 180-fold by 1 mM TB. Apoptosis was seen only above 0.6 mM TB (5-fold increase). Studies with caspase inhibitors revealed that TB mediated cell death was linked to up-regulation of caspases 3 and 8. Our results indicate that TB-induced differentiation promotes apoptosis in LS 174T cells and may explain the mode of action of TB finally resulting in an arrest of tumor cell growth.


Asunto(s)
Adenocarcinoma/patología , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Neoplasias del Colon/patología , Triglicéridos/farmacología , Adenocarcinoma/metabolismo , Fosfatasa Alcalina/metabolismo , Apoptosis/fisiología , Inhibidores de Caspasas , Caspasas/metabolismo , División Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/fisiología
17.
J Invest Dermatol ; 128(4): 890-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18049454

RESUMEN

Currently, most medical gloves are produced with a low content of natural rubber latex (NRL) protein. However, they may be substituted by proteins of foreign origin to maintain specific properties of the material. The aim of this study was to investigate the allergenicity and immunogenicity of unexpected proteins (i.e., soy and casein) compared with NRL proteins in a murine model in BALB/c mice. All respective allergen sources (extracts from three brands of NRL gloves, soy, and casein) were able to induce significant allergen-specific IgE and IgG(1) responses. On average, the highest IgE induction occurred after immunization with NRL, followed by soy and casein. Certain individuals from each treatment group exhibited levels of specific IgE as high as due to NRL. To analyze further specific IgE responses on a single allergen level, we established a microarray based on recombinant allergens for allergen-specific murine IgE detection. Besides specific IgE against rHev b 3, -6, -7, -8, and -11, specific IgE against kappa-casein could be detected in mice immunized with NRL glove extract, indicating a sensitization potential of the contained foreign protein. The substitution of genuine latex proteins by proteins of foreign origin may lead to a shift and de novo increase in sensitization to the finished products.


Asunto(s)
Alérgenos/inmunología , Guantes Quirúrgicos/efectos adversos , Hipersensibilidad Inmediata/inmunología , Inmunoglobulina E/sangre , Proteínas/inmunología , Alérgenos/genética , Alérgenos/aislamiento & purificación , Animales , Caseínas/inmunología , Femenino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Análisis por Matrices de Proteínas , Proteínas/aislamiento & purificación , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas de Soja/inmunología
18.
Anal Chem ; 79(1): 60-70, 2007 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-17194122

RESUMEN

A method for simultaneous and referenced 2D mapping of pH and pO2 is described. The experimental setup combines a fast gateable CCD camera as detector, a LED as excitation light source and a single-layer sensor membrane as optical transducer. The planar optode comprises a lipophilic fluorescein derivative (lifetime approximately 5 ns) and platinum(II) mesotetrakis(pentafluorophenyl)porphyrin (approximately 70 micros in the absence of a quencher) immobilized in a hydrogel matrix. Depending on the fluorescent pH indicator, a pH transition in the physiological range (pH 6-pH 8) or in the near-basic region (pH 7-pH 9) can be achieved. The measuring scheme involves the time-resolved acquisition of images in three windows during a series of square-shaped excitation pulses. A method allowing the calculation of both parameters from these three images is presented. The pH/pO2 hybrid sensor incorporating the pH indicator 2',7'-dihexyl-5(6)-N-octadecyl-carboxamidofluorescein was characterized in detail. The pH and pO2 were determined with a maximum deviation of 0.03 pH unit and 6.5 hPa pO2, respectively, within the range of pH 7.6-pH 8.7 and 0-200 hPa pO2 in test measurements. The ionic strength (IS) cross-sensitivity was found to be relatively small (pH/IS < 3.5 x 10(-4) mM(-1) and pO2/IS <-0.053 hPa mM(-1) at a transition from 0.5 to 0.1 M IS). Whereas a strong temperature effect on the sensor signal was observed (DeltapH/DeltaT = 0.011-0.034 K-1 and DeltapO2/DeltaT = 1.85-7.17 hPa K-1 in the range from 277 to 308 K). Examples of pH/pO2 images obtained in natural marine sediment are presented.

19.
Analyst ; 130(6): 907-16, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15912240

RESUMEN

In this work we present optical pH sensors especially designed for pH measurements in marine environment. Embedded in an uncharged, highly proton-permeable hydrogel matrix, the two novel lipophilic carboxyfluorescein derivatives 2',7'-dihexyl-5(6)-N-octadecyl-carboxamidofluorescein (DHFA) and 2',7'-dihexyl-5(6)-N-octadecyl-carboxamidofluorescein ethyl ester (DHFAE) have apparent dissociation constants of ca. 8.4. The pH transition range of the sensors perfectly matches the pH range occurring in seawater and marine sediment (ca. pH 7.2-9.2). The cross-sensitivity towards ionic strength (IS) was found to be low for DHFA-containing membranes and was even negligible when using DHFAE as indicator. The quantum yield (QY) of DHFA (0.94(basic)) is similar to that of fluorescein (0.97(basic)). QYs of 0.62(basic) and 0.22(acidic) were found for DHFAE. The optical properties of the indicators enable referenced measuring schemes. Lactonisation of the DHFAE chromophore is prevented by esterification of the carboxyl group in 2 position. Thus, internally referenced dual wavelength measurements are possible since the emission maxima of the basic and acidic form of DHFAE differ by 30 nm. Dual lifetime referenced (DLR) measurements were made with pH sensors incorporating ruthenium-(II)-tris-4,7-diphenyl-1,10-phenanthroline (Ru(dpp)(3))-containing reference particles in addition to the indicator. This type of sensor can be applied for pH imaging or in phase-modulation measurements of pH.


Asunto(s)
Concentración de Iones de Hidrógeno , Agua de Mar/química , Fluoresceínas , Sedimentos Geológicos/química , Hidrogel de Polietilenoglicol-Dimetacrilato , Indicadores y Reactivos
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