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1.
Sci Rep ; 12(1): 3622, 2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-35256671

RESUMEN

Pertussis is a severe respiratory tract infection caused by Bordetella pertussis. This bacterium infects the ciliated epithelium of the human airways. We investigated the epithelial cell response to B. pertussis infection in primary human airway epithelium (HAE) differentiated at air-liquid interface. Infection of the HAE cells mimicked several hallmarks of B. pertussis infection such as reduced epithelial barrier integrity and abrogation of mucociliary transport. Our data suggests mild immunological activation of HAE by B. pertussis indicated by secretion of IL-6 and CXCL8 and the enrichment of genes involved in bacterial recognition and innate immune processes. We identified IL-1ß and IFNγ, present in conditioned media derived from B. pertussis-infected macrophage and NK cells, as essential immunological factors for inducing robust chemokine secretion by HAE in response to B. pertussis. In transwell migration assays, the chemokine-containing supernatants derived from this HAE induced monocyte migration. Our data suggests that the airway epithelium on its own has a limited immunological response to B. pertussis and that for a broad immune response communication with local innate immune cells is necessary. This highlights the importance of intercellular communication in the defense against B. pertussis infection and may assist in the rational design of improved pertussis vaccines.


Asunto(s)
Bordetella pertussis , Tos Ferina , Bordetella pertussis/genética , Epitelio , Humanos , Inmunidad Innata , Sistema Respiratorio , Tos Ferina/microbiología
2.
PLoS One ; 10(6): e0127969, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26046664

RESUMEN

Currently licensed influenza vaccines mainly induce antibodies against highly variable epitopes. Due to antigenic drift, protection is subtype or strain-specific and regular vaccine updates are required. In case of antigenic shifts, which have caused several pandemics in the past, completely new vaccines need to be developed. We set out to develop a vaccine that provides protection against a broad range of influenza viruses. Therefore, highly conserved parts of the influenza A virus (IAV) were selected of which we constructed antibody and T cell inducing peptide-based vaccines. The B epitope vaccine consists of the highly conserved HA2 fusion peptide and M2e peptide coupled to a CD4 helper epitope. The T epitope vaccine comprises 25 overlapping synthetic long peptides of 26-34 amino acids, thereby avoiding restriction for a certain MHC haplotype. These peptides are derived from nucleoprotein (NP), polymerase basic protein 1 (PB1) and matrix protein 1 (M1). C57BL/6 mice, BALB/c mice, and ferrets were vaccinated with the B epitopes, 25 SLP or a combination of both. Vaccine-specific antibodies were detected in sera of mice and ferrets and vaccine-specific cellular responses were measured in mice. Following challenge, both mice and ferrets showed a reduction of virus titers in the lungs in response to vaccination. Summarizing, a peptide-based vaccine directed against conserved parts of influenza virus containing B and T cell epitopes shows promising results for further development. Such a vaccine may reduce disease burden and virus transmission during pandemic outbreaks.


Asunto(s)
Epítopos de Linfocito B/inmunología , Epítopos de Linfocito T/inmunología , Vacunas contra la Influenza/inmunología , Pulmón/virología , Vacunas de Subunidad/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales/inmunología , Bases de Datos Factuales , Perros , Femenino , Hurones , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Subtipo H5N1 del Virus de la Influenza A/metabolismo , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Vacunas de Subunidad/síntesis química , Vacunas de Subunidad/química , Carga Viral , Proteínas de la Matriz Viral/química , Proteínas de la Matriz Viral/inmunología
3.
Clin Immunol ; 148(1): 92-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23669455

RESUMEN

Hematopoietic stem cell transplantation (HSCT) is frequently complicated by viral reactivations. Early diagnosis of viral reactivations and preemptive therapy relies on frequent viralload monitoring. An easy marker of effective cytotoxicity in lymphopenia is lacking and therefore we studied perforin-expression in CD8+T-cells in children following HSCT. Prospectively, we weekly monitored viral loads and perforin-expression of CD8+T-cells in whole blood by FACS, until 4months after HSCT in children. 27 patients were included (median age 4,3, range 0.3-20,1years) of whom 19 developed viral reactivations. These patients showed higher percentages of perforin-expressing CD8+T-cells (17,2%, range 0-63%) than those without (6,8%; range 0-16%) (p=0.001). The increased percentage of perforin-expressing CD8+T-cells coincided with a decrease in viral load with a median interval between maximum viral load and maximum level of perforin-expression of 0,4weeks (range 0.1-7.1). We conclude that perforin-expression in CD8+T-cells may be a marker for effective antiviral T-cell reconstitution early after HSCT in children.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Trasplante de Células Madre Hematopoyéticas , Herpesvirus Humano 6/fisiología , Perforina/biosíntesis , Perforina/sangre , Infecciones por Roseolovirus/inmunología , Adolescente , Linfocitos T CD8-positivos/virología , Niño , Preescolar , Estudios de Cohortes , ADN Viral/química , ADN Viral/genética , Citometría de Flujo , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/inmunología , Humanos , Inmunofenotipificación , Lactante , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones por Roseolovirus/sangre , Infecciones por Roseolovirus/virología , Estadísticas no Paramétricas , Activación Viral , Adulto Joven
4.
Clin Infect Dis ; 50(5): 717-25, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20121571

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) and cytomegalovirus reactivations are frequent complications of hematopoeitic allogeneic stem cell transplantation (SCT) because of a lack of T cell control after immunosuppression. Early diagnosis of reactivation and subsequent preemptive therapy relies on frequent viral load measurement. Additional virus-specific T cell reconstitution data could improve the predictive value of viral load detection for viral complications after transplantation. Here, we studied perforin expression in CD8(+) T cells as a measure of cytotoxic T cell capacity in relation to the occurrence of viral reactivation. METHODS: In a prospective study, we monitored 40 patients during the first 3 months after transplantation and measured viral loads in combination with intracellular perforin expression in CD8(+) T cells. RESULTS: Median perforin expression in CD8(+) T cells throughout follow-up was higher in patients with viral reactivations than in patients without viral reactivations (4.9% vs 2.3%; P = .001). The median percentage of perforin-expressing CD8(+) T cells in patients with high viral reactivations exceeding 1000 copies/mL (10.7%) was statistically significantly higher than that in patients with minor reactivations of 50-1000 copies (4.0%), that in patients with detectable EBV loads that did not exceed the detection limit of 50 copies/mL (2.9%), and that in patients without reactivations (0.8%). Patients with high viral reactivations reached a high percentage of perforin-expressing CD8(+) T cells (>10.2%) more often and faster than did patients with low viral loads (1000 copies/mL) or without viral reactivations. High perforin expression preceded high viral loads. CONCLUSION: Perforin-expressing CD8(+) T cells may be useful as an easy-to-measure prognostic marker for identifying patients at risk for severe viral reactivation very soon after SCT.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Virus de Epstein-Barr/inmunología , Perforina/biosíntesis , Trasplante de Células Madre/efectos adversos , Activación Viral/inmunología , Adulto , Anciano , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Virus de Epstein-Barr/diagnóstico , Femenino , Herpesvirus Humano 4/inmunología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Adulto Joven
5.
J Hum Evol ; 55(5): 898-907, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18929395

RESUMEN

The "Red Lady" partial human skeleton found at Goat's Hole, Paviland, in south Wales by William Buckland in 1823 is one of the iconic relics of the British Paleolithic. Originally thought to be Roman, a Paleolithic age has been suspected from the middle of the 19th century. Several attempts have been made at directly radiocarbon dating the "Red Lady," and here we report new determinations that suggest that it is, by a significant margin, the oldest of a group of 'rich,' Mid-Upper Paleolithic burials. We list similar Gravettian-aged burials from Europe, which have been dated recently for comparison. In this paper, we also reconsider the chronology of human use of the cave, apart from as a burial location.


Asunto(s)
Antropología Cultural/métodos , Antropología Física/métodos , Arqueología/métodos , Huesos/química , Cronología como Asunto , Ultrafiltración/métodos , Entierro , Femenino , Humanos , Datación Radiométrica/métodos , Gales
6.
J Hum Evol ; 49(3): 390-4, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15975629

RESUMEN

We report here on direct evidence for the intensive consumption of marine foods by anatomically modern humans at approximately 12,000 years ago. We undertook isotopic analysis of bone collagen from three humans, dating to the late Palaeolithic, from the site of Kendrick's Cave in North Wales, UK. The isotopic measurements of their bone collagen indicated that ca. 30% of their dietary protein was from marine sources, which we interpret as likely being high trophic level marine organisms such as marine mammals. This indicates that towards the end of the Pleistocene modern humans were pursuing a hunting strategy that incorporated both marine and terrestrial mammals. This is the first occurrence of the intensive use of marine resources, specifically marine mammals, that becomes even more pronounced in the subsequent Mesolithic period.


Asunto(s)
Evolución Biológica , Huesos/química , Colágeno/análisis , Dieta , Animales , Caniformia , Isótopos de Carbono , Ciervos , Peces , Fósiles , Humanos , Mamíferos , Isótopos de Nitrógeno , Conducta Predatoria , Alimentos Marinos , Mariscos , Gales
7.
Genet. mol. res. (Online) ; 4(3): 543-552, 2005. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-444957

RESUMEN

Reconfigurable systolic arrays can be adapted to efficiently resolve a wide spectrum of computational problems; parallelism is naturally explored in systolic arrays and reconfigurability allows for redefinition of the interconnections and operations even during run time (dynamically). We present a reconfigurable systolic architecture that can be applied for the efficient treatment of several dynamic programming methods for resolving well-known problems, such as global and local sequence alignment, approximate string matching and longest common subsequence. The dynamicity of the reconfigurability was found to be useful for practical applications in the construction of sequence alignments. A VHDL (VHSIC hardware description language) version of this new architecture was implemented on an APEX FPGA (Field programmable gate array). It would be several magnitudes faster than the software algorithm alternatives.


Asunto(s)
Humanos , Algoritmos , Alineación de Secuencia/métodos , Biología Computacional/métodos , Programas Informáticos , Factores de Tiempo , Modelos Genéticos , Simulación por Computador
9.
AJR Am J Roentgenol ; 170(5): 1299-302, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9574606

RESUMEN

OBJECTIVE: Because the presence of echogenic fluid on transvaginal sonography has been shown to correlate well with hemoperitoneum in patients with possible ectopic pregnancy, the aim of this study was to compare echogenic fluid on sonography with the results of culdocentesis in predicting hemoperitoneum. MATERIALS AND METHODS: Free fluid on transvaginal sonography and the results of culdocentesis were correlated with the presence or absence of hemoperitoneum in 46 patients at surgery. Forty ectopic pregnancies and six nonectopic pregnancies were found. Echogenic fluid was the criterion used to establish hemoperitoneum on sonography. For statistical analysis, negative and nondiagnostic culdocentesis results were combined. The sensitivity, specificity, and positive and negative predictive values of each diagnostic technique were compared. RESULTS: In 40 of 46 patients with ectopic pregnancy, the sensitivity and specificity of echogenic fluid for establishing hemoperitoneum were 100% and 100%, respectively, compared with 66% and 80%, respectively, for culdocentesis. More important, the negative predictive value of a nondiagnostic culdocentesis was 25% compared with 100% for echogenic fluid in the ectopic subgroup of patients. In two patients with incomplete abortions, sonography failed to detect small amounts of hemoperitoneum at surgery performed 4 hr and 7 days after sonography. CONCLUSION: Sonography is more sensitive than culdocentesis in the detection of hemoperitoneum. Culdocentesis is invasive, and nondiagnostic results cannot be used to exclude hemoperitoneum. Culdocentesis should play no role in the evaluation of ectopic pregnancy except in the unusual circumstance in which high-resolution sonography cannot be readily performed.


Asunto(s)
Hemoperitoneo/diagnóstico por imagen , Paracentesis , Embarazo Ectópico/diagnóstico por imagen , Ultrasonografía Prenatal , Vagina/patología , Aborto Incompleto/diagnóstico , Aborto Incompleto/diagnóstico por imagen , Adolescente , Adulto , Apendicitis/diagnóstico , Apendicitis/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Predicción , Hemoperitoneo/diagnóstico , Humanos , Quistes Ováricos/diagnóstico , Quistes Ováricos/diagnóstico por imagen , Valor Predictivo de las Pruebas , Embarazo , Embarazo Ectópico/diagnóstico , Estudios Retrospectivos , Sensibilidad y Especificidad , Vagina/diagnóstico por imagen
10.
Dent Clin North Am ; 37(3): 367-90, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8348992

RESUMEN

Devices used to increase retention of restorations to severely damaged posterior teeth are described, with an emphasis on pins and dowels. Advantages and disadvantages of different techniques and measures to help prevent and correct problems are presented.


Asunto(s)
Pins Dentales , Retención de Prótesis Dentales/instrumentación , Restauración Dental Permanente/instrumentación , Técnica de Perno Muñón/instrumentación , Diente Premolar , Recubrimiento Dental Adhesivo , Retención de Prótesis Dentales/métodos , Coronas con Frente Estético , Humanos , Diente Molar
11.
J Prosthet Dent ; 66(3): 303-9, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1800724

RESUMEN

A type III gold alloy and six different ceramic surfaces were secured in an abrasion machine opposing extracted teeth to determine their relative abrasiveness and resistance to wear. The rankings of restorative materials from least abrasive to most abrasive were: gold alloy, polished; cast ceramic, polished; porcelain, polished; cast ceramic, polished and shaded; porcelain, polished and glazed; cast ceramic, cerammed skin shaded; and cast ceramic, cerammed skin unshaded. The ranking of materials from most wear-resistant to least wear-resistant was: gold alloy, cast ceramic cerammed, cast ceramic cerammed and shaded, porcelain polished, porcelain glazed, cast ceramic polished and shaded, and cast ceramic polished.


Asunto(s)
Cerámica/química , Porcelana Dental/química , Aleaciones de Oro/química , Abrasión de los Dientes/patología , Análisis de Varianza , Pulido Dental , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Tamaño de los Órganos , Propiedades de Superficie , Diente/patología
12.
J Prosthet Dent ; 64(2): 127-30, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2202812

RESUMEN

The laboratory procedures for making a Hi-ceram porcelain anterior reserve three-quarter crown are described. A core of high-fusing aluminum oxide is used as a coping on which tooth contours are restored with a compatible porcelain. Standard dental laboratory equipment is used and the technique can be quickly learned by any experienced ceramics technician.


Asunto(s)
Óxido de Aluminio , Aluminio , Coronas , Porcelana Dental , Incisivo , Técnica de Colado Dental , Diseño de Dentadura , Humanos , Laboratorios Odontológicos
17.
J Prosthet Dent ; 61(1): 4-6, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2644421

RESUMEN

A new preparation design of the ceramic reverse three-quarter crown for anterior teeth offers a way to improve the appearance of anterior teeth with slight to moderate structural damage. Advantages and indications of the new design are discussed.


Asunto(s)
Coronas , Porcelana Dental , Diseño de Dentadura , Preparación de la Cavidad Dental/métodos , Coronas con Frente Estético , Retención de Dentadura , Humanos , Incisivo
19.
J Prosthet Dent ; 60(4): 433-5, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3054064

RESUMEN

A method has been described by which a paste of shoulder porcelain and light-curing resin is used to correct deficient porcelain margins. The resin-bonded porcelain is fired in an oven for final hardening.


Asunto(s)
Coronas , Recubrimiento Dental Adhesivo , Porcelana Dental , Coronas con Frente Estético , Diseño de Dentadura , Humanos , Pomadas , Resinas Sintéticas , Propiedades de Superficie
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