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1.
J Eur Acad Dermatol Venereol ; 37(9): 1799-1810, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37210651

RESUMEN

BACKGROUND: Monoclonal antibodies, such as cemiplimab and pembrolizumab, against the programmed death receptor (PD)-1 have become the current standard of care and first-line treatment of advanced cutaneous squamous cell carcinoma (cSCC), proving remarkable clinical benefit and acceptable safety. OBJECTIVES: To assess efficacy and safety of the anti-PD-1 antibody nivolumab in patients with locally advanced and metastatic cSCC. METHODS: Patients received open-label nivolumab 240 mg intravenously every 2 weeks for up to 24 months. Patients with concomitant haematological malignancies (CHMs), either non-progressing or stable under active therapy, were eligible for inclusion. RESULTS: Of 31 patients with a median age of 80 years, 22.6% of patients achieved an investigator assessed complete response, resulting in an objective response rate (ORR) of 61.3% and a disease control rate (DCR) of 64.5%. Progression-free survival (PFS) was 11.1 months, and the median overall survival (OS) was not reached after 24 weeks of therapy. Median follow-up was 23.82 months. Subgroup analysis of the CHM cohort (n = 11; 35%) revealed an ORR of 45.5%, a DCR of 54.5%, a median PFS of 10.9 months, and median OS of 20.7 months. Treatment related adverse events were reported in 58.1% of all patients (19.4% grade 3, the remaining grade 1 or 2). PD-L1 expression and CD-8+ T-cell infiltration did not significantly correlate with clinical response, although a trend towards a shorter PFS of 5.6 months was observed with PD-L1 negativity and low CD8+ intratumoral infiltration. CONCLUSION: This study demonstrated robust clinical efficacy of nivolumab in patients with locally advanced and metastatic cSCCs and a tolerability comparable to data of other anti-PD-1 antibodies. Favourable outcomes were obtained despite involving the oldest hitherto reported study cohort for anti-PD-1 antibodies and a significant proportion of CHM patients prone to high risk tumours and an aggressive course otherwise typically excluded from clinical trials.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Hematológicas , Neoplasias Cutáneas , Humanos , Anciano de 80 o más Años , Nivolumab/uso terapéutico , Nivolumab/efectos adversos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/inducido químicamente , Antígeno B7-H1 , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/inducido químicamente
2.
Opt Express ; 24(22): 25608-25618, 2016 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-27828496

RESUMEN

In this paper, we demonstrate an integrated microwave phoneeded for beamtonics phased array antenna feeder at 60 GHz with a record-low footprint. Our design is based on ultra-compact plasmonic phase modulators (active area <2.5µm2) that not only provide small size but also ultra-fast tuning speed. In our design, the integrated circuit footprint is in fact only limited by the contact pads of the electrodes and by the optical feeding waveguides. Using the high speed of the plasmonic modulators, we demonstrate beam steering with less than 1 ns reconfiguration time, i.e. the beam direction is reconfigured in-between 1 GBd transmitted symbols.

3.
Acta Anaesthesiol Scand ; 60(4): 492-501, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26489399

RESUMEN

BACKGROUND: Perioperative high-dose oxygen (O2 ) exposure can cause hyperoxia. While the effect of constant hyperoxia on the vascular endothelium has been investigated to some extent, the impact of cyclic hyperoxia largely remains unknown. We hypothesized that cyclic hyperoxia would induce more injury than constant hyperoxia to human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were exposed to cyclic hyperoxia (5-95% O2 ) or constant hyperoxia (95% O2 ), normoxia (21% O2 ), and hypoxia (5% O2 ). Cell growth, viability (Annexin V/propidium iodide and 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, MTT) lactate dehydrogenase (LDH), release, cytokine (interleukin, IL and macrophage migration inhibitory factor, MIF) release, total antioxidant capacity (TAC), and superoxide dismutase activity (SOD) of cell lysate were assessed at baseline and 8, 24, and 72 h. A signal transduction pathway finder array for gene expression analysis was performed after 8 h. RESULTS: Constant and cyclic hyperoxia-induced gradually detrimental effects on HUVECs. After 72 h, constant or cyclic hyperoxia exposure induced change in cytotoxic (LDH +12%, P = 0.026; apoptosis +121/61%, P < 0.01; alive cells -15%, P < 0.01; MTT -16/15%, P < 0.01), inflammatory (IL-6 +142/190%, P < 0.01; IL-8 +72/43%, P < 0.01; MIF +147/93%, P < 0.01), or redox-sensitive (SOD +278%, TAC-25% P < 0.01) markers. Gene expression analysis revealed that constant and cyclic hyperoxia exposure differently activates oxidative stress, nuclear factor kappa B, Notch, and peroxisome proliferator-activated receptor pathways. CONCLUSIONS: Extreme hyperoxia exposure induces inflammation, apoptosis and cell death in HUVECs. Although our findings cannot be transferred to clinical settings, results suggest that hyperoxia exposure may cause vascular injury that could play a role in determining perioperative outcome.


Asunto(s)
Apoptosis , Hiperoxia/complicaciones , Inflamación/etiología , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Hiperoxia/patología , Transcriptoma
4.
Opt Express ; 23(23): 29746-57, 2015 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-26698457

RESUMEN

Plasmonic modulators might pave the way for a new generation of compact low-power high-speed optoelectronic devices. We introduce an extremely compact transmitter based on plasmonic Mach-Zehnder modulators offering a capacity of 4 × 36 Gbit/s on a footprint that is only limited by the size of the high-speed contact pads. The transmitter array is contacted through a multicore fiber with a channel spacing of 50 µm.

5.
Br J Dermatol ; 172(6): 1642-1645, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25420590

RESUMEN

Epidermal naevi (EN) are considered mosaic disorders. Postzygotic mutations are thought to occur during early embryogenesis. They are usually arranged along Blaschko's lines and tend to be noted either at birth or shortly thereafter. Skin tumours arising on EN are occasionally reported, with ongoing discussion as to whether these are collision tumours or a malignant transformation of the EN. We describe a 76-year-old woman with segmentally arranged seborrhoeic keratoses that showed impending atypia and, in one lesion, even overt malignant transformation. In biopsies from various lesions we found FGFR3 and PIK3CA hotspot mutations but there was no consistent pattern of mutations explaining the premalignant or malignant growth. So far it is unclear whether the precancerous changes as noted in this elderly patient can be taken as an unusual manifestation of one of the established types of EN, or whether this may represent a separate disorder that could be called 'SASKIA naevus'. The acronym would stand for segmentally arranged seborrhoeic keratoses with impending atypia.


Asunto(s)
Carcinoma de Células Escamosas/genética , Queratosis Seborreica/genética , Mutación/genética , Fosfatidilinositol 3-Quinasas/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Neoplasias Cutáneas/genética , Anciano , Carcinoma de Células Escamosas/patología , Fosfatidilinositol 3-Quinasa Clase I , Femenino , Humanos , Queratosis Seborreica/patología , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Neoplasias Cutáneas/patología
6.
Pathologe ; 35(5): 413-23, 2014 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-25187080

RESUMEN

Seborrheic keratosis (SK) and epidermal nevi (EN) represent benign skin tumors and congenital lesions, respectively. Oncogenic mutations are fundamentally involved in their pathogenesis and SK is characterized by a broad spectrum of somatic mutations in the FGFR3, PIK3CA, RAS, AKT1 and EGFR genes. In contrast to malignant tumors, SK is genetically stable without alterations of tumor suppressor genes. The ENs are caused by postzygotic activating hot spot mutations in FGFR3, PIK3CA and particularly HRAS, resulting in a genetic mosaicism. The size of the lesions and the differentiation potential of the mutated cell into various tissue types depends on the time point of the mutation during embryogenesis. The genetic mosaic may predispose to a later growth of benign and malignant (adnexal) tumors.


Asunto(s)
Queratosis Seborreica/genética , Neoplasias Cutáneas/genética , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Análisis Mutacional de ADN , Predisposición Genética a la Enfermedad/genética , Humanos , Queratosis Seborreica/clasificación , Mosaicismo , Nevo/clasificación , Nevo/genética , Oncogenes/genética , Mutación Puntual/genética , Piel/patología , Neoplasias Cutáneas/clasificación
7.
Resuscitation ; 194: 110089, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38110144

RESUMEN

BACKGROUND: Current resuscitation guidelines recommend that skilled persons could use ultrasound to detect reversible causes during cardiopulmonary resuscitation (CPR) where the examination can be safely integrated into the Advanced Life Support (ALS) algorithm. However, in a prehospital setting performing and rapidly interpreting ultrasound can be challenging for physicians. Implementing remote, expert-guided, and real-time transmissions of ultrasound examinations offers the opportunity for tele-support, even during an out-of-hospital cardiac arrest (OHCA). The aim of this feasibility study was to evaluate the impact of tele-supported ultrasound in ALS on hands-off time during an OHCA. METHODS: In an urban setting, physicians performed point-of-care ultrasound (POCUS) on patients during OHCA using a portable device, either with tele-support (n = 30) or without tele-support (n = 12). Where tele-support was used, the ultrasound image was transmitted via a remote real-time connection to an on-call specialist in anaesthesia and intensive care medicine with an advanced level of critical care ultrasound expertise. The primary safety endpoint of this study was to evaluate whether POCUS can be safely integrated into the algorithm, and to provide an analysis of hands-off time before, during, and after POCUS during OHCA. RESULTS: In all 42 cases it was possible to perform POCUS during regular rhythm analyses, and no additional hands-off time was required. In 40 of these 42 cases, the physicians were able to perform POCUS during a single regular rhythm analysis, with two periods required only in two cases. The median hands-off time during these rhythm analyses for POCUS with tele-support was 10 (8-13) seconds, and 11 (9-14) seconds for POCUS without tele-support. Furthermore, as a result of POCUS, in a quarter of all cases the physician on scene altered their diagnosis of the primary suspected cause of cardiac arrest, leading to a change in treatment strategy. CONCLUSIONS: This feasibility study demonstrated that POCUS with tele-support can be safely performed during OHCA in an urban environment. Trial Registration (before patient enrolment): ClinicalTrials.gov, NCT04817475.


Asunto(s)
Reanimación Cardiopulmonar , Servicios Médicos de Urgencia , Paro Cardíaco Extrahospitalario , Humanos , Reanimación Cardiopulmonar/métodos , Servicios Médicos de Urgencia/métodos , Estudios de Factibilidad , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Paro Cardíaco Extrahospitalario/terapia , Sistemas de Atención de Punto
9.
Hautarzt ; 64(2): 110-3, 2013 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-23354656

RESUMEN

Erythema scarlatiniforme desquamativum generalisatum (Féréol-Besnier disease) is a rare skin disease characterized by generalized erythematous rash with subsequent desquamation. An 86-year-old woman presented with generalized erythema followed by an extensive, scarlatiniform peeling especially of the hands and feet. This generalized episode may be followed by erythema scarlatiniforme desquamativum localisatum recidivans, which is a recurring variant of the disease, localized to the hands and feet.


Asunto(s)
Eritema/diagnóstico , Dermatosis del Pie/diagnóstico , Dermatosis de la Mano/diagnóstico , Ictiosis/diagnóstico , Anciano de 80 o más Años , Biopsia , Fármacos Dermatológicos/uso terapéutico , Diagnóstico Diferencial , Quimioterapia Combinada , Eritema/tratamiento farmacológico , Eritema/patología , Femenino , Dermatosis del Pie/tratamiento farmacológico , Dermatosis del Pie/patología , Dermatosis de la Mano/tratamiento farmacológico , Dermatosis de la Mano/patología , Humanos , Ictiosis/tratamiento farmacológico , Ictiosis/patología , Piel/patología
10.
Br J Dermatol ; 166(4): 784-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22188534

RESUMEN

BACKGROUND: Benign lichenoid keratoses (BLKs) are solitary skin lesions which have been proposed to represent a regressive form of pre-existent epidermal tumours such as solar lentigo or seborrhoeic keratosis. However, the genetic basis of BLK is unknown. OBJECTIVES: FGFR3, PIK3CA and RAS mutations have been shown to be involved in the pathogenesis of seborrhoeic keratosis and solar lentigo. We thus investigated whether these mutations are also present in BLK. METHODS: After manual microdissection and DNA isolation, 52 BLKs were screened for FGFR3, PIK3CA and RAS hotspot mutations using SNaPshot(®) multiplex assays. RESULTS: We identified 6/52 (12%) FGFR3 mutations, 10/52 (19%) PIK3CA mutations, 6/52 (12%) HRAS mutations and 2/52 (4%) KRAS mutations. FGFR3 and RAS mutations were mutually exclusive. One BLK showed a simultaneous PIK3CA and HRAS mutation. In nine BLKs with a mutation, nonlesional control tissue from the epidermal margin and the dermal lymphocytic infiltrate were wild-type, indicating that these mutations are somatic. To demonstrate that these findings are specific, 10 samples of lichen planus were analysed without evidence for FGFR3, PIK3CA or RAS mutations. CONCLUSIONS: Our results indicate that FGFR3, PIK3CA and RAS mutations are present in approximately 50% of BLKs. These findings support the concept on the molecular genetic level that at least a proportion of BLKs represents regressive variants resulting from former benign epidermal tumours such as seborrhoeic keratosis and solar lentigo.


Asunto(s)
Queratosis/genética , Erupciones Liquenoides/genética , Mutación/genética , Fosfatidilinositol 3-Quinasas/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Fosfatidilinositol 3-Quinasa Clase I , Femenino , Humanos , Liquen Plano/genética , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas , Proteínas Proto-Oncogénicas p21(ras)
11.
Internist (Berl) ; 53(4): 467-73, 2012 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-22274304

RESUMEN

We report on a 72-year-old female patient with multiple myeloma who presented with alopecia and eye-catching alterations of the skin and the nails. A biopsy of the skin could confirm the diagnosis of immunoglobulin light chain (AL) amyloidosis, which was also suspected of having affected other organs. After six cycles of a cytoreductive therapy with bortezomib and dexamethasone a very good partial response of the multiple myeloma was seen and an improvement in the skin and nail alterations could be achieved.


Asunto(s)
Amiloidosis/tratamiento farmacológico , Amiloidosis/etiología , Mieloma Múltiple/complicaciones , Mieloma Múltiple/tratamiento farmacológico , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/etiología , Anciano , Amiloidosis/diagnóstico , Antineoplásicos/administración & dosificación , Antineoplásicos Hormonales/administración & dosificación , Ácidos Borónicos/administración & dosificación , Bortezomib , Dexametasona/administración & dosificación , Diagnóstico Diferencial , Femenino , Humanos , Mieloma Múltiple/diagnóstico , Pirazinas/administración & dosificación , Enfermedades de la Piel/diagnóstico , Resultado del Tratamiento
12.
Clin Exp Allergy ; 41(1): 129-36, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21083775

RESUMEN

BACKGROUND: Allergy to kiwifruit is increasingly reported across Europe. Currently, the reliability of its diagnosis by the measurement of allergen-specific IgE with extracts or by skin testing with fresh fruits is unsatisfying. OBJECTIVE: To evaluate the usefulness of a component-based allergen microarray for the diagnosis of kiwifruit allergy in a large group of patients. METHODS: With an allergen microarray, we measured specific IgE and IgG4 levels to a panel of nine kiwifruit allergens in sera of 237 individuals with kiwifruit allergy. Sera from 198 allergic patients without kiwifruit allergy served as controls. Furthermore, we determined the extent of sensitization to latex. RESULTS: The panel of kiwifruit allergens showed a diagnostic sensitivity of 66%, a specificity of 56% and a positive predictive value of 73%. Sera from kiwifruit-allergic patients contained significantly more frequently Act d 1-specific IgE than sera from control patients. Furthermore, 51% of the positive sera contained IgE directed to a single allergen, namely Act d 1 (45%), Act d 9 (27%) or Act d 7 (13%). Within the control group, 36% sera recognized a single allergen. Out of those, 48% were positive to the cross-reactive glycoallergen Act d 7, 43% to the profilin Act d 9 and only 5% to Act d 1. Allergen-specific IgG4 levels did not differ between kiwifruit-allergic and -tolerant patients. Kiwifruit- and latex-allergic patients contained Hev b 11-specific IgE significantly more frequently than latex-allergic patients without kiwifruit allergy. CONCLUSIONS: Act d 1 can be considered a marker allergen for genuine sensitization to kiwifruit. We demonstrated that a component-based kiwifruit allergen microarray would improve the prognostic value of in vitro diagnostic tests.


Asunto(s)
Actinidia/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Análisis por Matrices de Proteínas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alérgenos/inmunología , Niño , Preescolar , Cisteína Endopeptidasas/sangre , Cisteína Endopeptidasas/inmunología , Femenino , Hipersensibilidad a los Alimentos/inmunología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto Joven
13.
Br J Dermatol ; 164(4): 873-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21418173

RESUMEN

BACKGROUND: Eruptive Spitz naevi have been reported rarely in the literature. In solitary Spitz naevi, BRAF and HRAS mutations, as well as increased copy numbers of chromosome 11p have been identified. OBJECTIVES: To investigate the genetic changes underlying eruptive Spitz naevi. METHODS: We report on a 16-year-old boy who developed multiple disseminated eruptive Spitz naevi within a few months. We analysed BRAF, HRAS, KRAS and NRAS genes in 39 naevi from this patient for hotspot mutations. Furthermore, comparative genomic hybridization analysis was performed in three lesions. RESULTS: None of the Spitz naevi displayed a mutation in the analysed genes, and no chromosomal imbalances were observed. Conclusions Our results indicate that the typical genetic alterations described in solitary Spitz naevi appear to be absent in eruptive Spitz naevi. Yet unknown alternative genetic alterations must account for this rare syndrome.


Asunto(s)
Mutación , Nevo de Células Epitelioides y Fusiformes/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Adolescente , Análisis Mutacional de ADN , Genes ras , Humanos , Masculino , Nevo de Células Epitelioides y Fusiformes/patología
15.
Br J Dermatol ; 162(3): 508-12, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19845664

RESUMEN

BACKGROUND: Stucco keratosis (STK) and dermatosis papulosa nigra (DPN) are referred to as variants of seborrhoeic keratosis. However, the genetic alterations involved in the pathogenesis of these benign tumours are unknown. OBJECTIVES: Because FGFR3 and PIK3CA mutations have been reported to be involved in the pathogenesis of seborrhoeic keratosis, we analysed whether these mutations are also present in STK and DPN. Methods A SNaPshot multiplex assay was used for analysis of 11 previously described FGFR3 hotspot mutations. PIK3CA mutations were analysed by a SNaPshot assay covering five PIK3CA hotspot mutations. RESULTS: Five STK and two DPN samples were analysed. Three of five STK samples revealed a PIK3CA mutation (E542K, E545K), but no FGFR3 mutation was found. In contrast, both DPN samples harboured an FGFR3 mutation (R248C, S249C) but no PIK3CA mutation. Control tissues available for three samples did not show PIK3CA or FGFR3 mutations, excluding germline mutations and indicating a strong genotype-phenotype correlation between the mutation and the lesion. CONCLUSIONS: These results indicate that FGFR3 and PIK3CA mutations are involved in the pathogenesis of STK and DPN. The molecular genetic findings furthermore support the concept that both skin lesions are specific variants of seborrhoeic keratosis, sharing a common genetic background.


Asunto(s)
Queratosis Seborreica/genética , Fosfatidilinositol 3-Quinasas/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Adulto , Anciano , Fosfatidilinositol 3-Quinasa Clase I , Análisis Mutacional de ADN , Femenino , Humanos , Queratosis Seborreica/patología , Masculino , Persona de Mediana Edad , Mutación , Factores de Riesgo , Adulto Joven
17.
Pathologe ; 31 Suppl 2: 221-4, 2010 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-20711586

RESUMEN

Activating FGFR3 mutations have been identified in a variety of benign skin lesions (seborrheic keratosis, epidermal nevus, solar lentigo). However, the functional consequences of these mutations in the human epidermis are unknown. We therefore analyzed functional effects of the common R248C mutation in HaCaT keratinocytes. The cells were stably transduced with the R248C FGFR3 mutation or FGFR3-IIIb wildtype sequence using a retroviral system. The R248C mutant keratinocytes revealed significantly enhanced cell growth compared with wildtype cells after reaching confluence. Likewise, apoptosis and attachment to fibronectin were significantly reduced in mutant cells. In contrast, there was no difference regarding migration and oncogene-induced senescence. Gene expression analysis revealed only a few differentially expressed genes between mutant and wildtype HaCaT keratinocytes. ERK1/2 appear to be involved in the FGFR3-dependent signalling of R248C mutant keratinocytes. Our results indicate that an increased cell number at confluence along with reduced apoptosis may contribute to the growth of benign acanthotic tumors in the human epidermis.


Asunto(s)
Alelos , Apoptosis/genética , Adhesión Celular/genética , División Celular/genética , Análisis Mutacional de ADN , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Queratinocitos/patología , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Transducción de Señal/genética , Piel/patología
18.
Opt Express ; 17(17): 15186-200, 2009 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-19687997

RESUMEN

The development of photonic nano-structures can strongly benefit from full-field electromagnetic (EM) simulations. To this end, geometrical flexibility and accurate material modelling are crucial requirements set on the simulation method. This paper introduces a modular implementation of dispersive materials for time-domain EM simulations with focus on the Finite-Volume Time-Domain (FVTD) method. The proposed treatment can handle electric and magnetic dispersive materials exhibiting multi-pole Debye, Lorentz and Drude models, which can be mixed and combined without restrictions. The presented technique is verified in several illustrative examples, where the backscattering from dispersive spheres is calculated. The amount of flexibility and freedom gained from the proposed implementation will be demonstrated in the challenging simulation of the plasmonic resonance behavior of two gold nanospheres coupled in close proximity, where the dispersive characteristic of gold is approximated by realistic values in the optical frequency range.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Óptica y Fotónica , Algoritmos , Simulación por Computador , Campos Electromagnéticos , Modelos Estadísticos , Nanosferas/química , Dispersión de Radiación , Resonancia por Plasmón de Superficie , Factores de Tiempo
19.
Br J Dermatol ; 160(3): 546-51, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19076977

RESUMEN

BACKGROUND: Solar lentigines (SL) are frequent benign skin lesions appearing on sun-exposed areas especially in elderly people and therefore represent a hallmark of (photo)aged skin. It has been proposed that SL may subsequently evolve into adenoid seborrhoeic keratosis (SK). However, little is known about the genetic basis of SL. In human SK, FGFR3 and PIK3CA mutations have recently been identified. OBJECTIVES: To analyse SL for potential FGFR3 and PIK3CA mutations. METHODS: We screened 30 SL for FGFR3 mutations using a SNaPshot multiplex assay. For PIK3CA mutations we used direct sequencing of exon 9 and a SNaPshot assay for the H1047R hotspot mutation (exon 20). Because psoralen plus ultraviolet A (PUVA) lentigines show the V600E BRAF hotspot mutation, we additionally investigated this mutation in SL by allele-specific polymerase chain reaction. RESULTS: FGFR3 mutations were detected in five of 30 (17%) SL and PIK3CA mutations in two of 28 (7%) SL. None of 28 SL available for BRAF analysis revealed the V600E mutation. CONCLUSIONS: Our results suggest that FGFR3 and PIK3CA mutations are involved in the pathogenesis of SL. The occurrence of these mutations in both SL and SK suggests a common genetic basis. Our findings furthermore substantiate previous speculations that UV exposure may be a causative factor for FGFR3 and PIK3CA mutations in human skin.


Asunto(s)
Lentigo/genética , Mutación , Fosfatidilinositol 3-Quinasas/genética , Trastornos por Fotosensibilidad/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Adulto , Anciano , Fosfatidilinositol 3-Quinasa Clase I , Análisis Mutacional de ADN/métodos , Femenino , Humanos , Lentigo/patología , Masculino , Persona de Mediana Edad , Trastornos por Fotosensibilidad/patología , Proteínas Proto-Oncogénicas B-raf/genética , Envejecimiento de la Piel/genética
20.
Brain ; 131(Pt 6): 1455-63, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18474519

RESUMEN

B cells are increasingly recognized as major players in multiple sclerosis pathogenesis. The BAFF/APRIL system is crucial for B cell homoeostasis and may drive B cell-dependent autoimmunity. We asked whether this system is affected by Interferon (IFN)-beta therapy. We analysed transcription of the ligands (BAFF, APRIL, TWE-PRIL) and the corresponding receptors (BAFF-R, TACI and BCMA) by TaqMan-PCR ex vivo in whole blood and in immune cell subsets purified from IFN-beta-treated multiple sclerosis patients. Serum BAFF concentrations were determined by ELISA. This cross-sectional study involved 107 donors. IFN-beta therapy strongly induced BAFF transcription proportionally to the IFN-beta biomarker MxA in monocytes and granulocytes in vivo. BAFF serum concentrations were elevated in IFN-beta-treated multiple sclerosis patients to a similar level as observed in SLE patients. In cultured PBMC, neutrophils, fibroblasts and astrocytes, BAFF was induced by IFN-beta concentrations similar to those reached in vivo in treated multiple sclerosis patients. BAFF turned out to be the main regulated element of the BAFF/APRIL system. In untreated multiple sclerosis patients, there was no BAFF increase as compared to healthy controls. Our study reveals a complex situation. We show that IFN-beta therapy induces a potent B cell survival factor, BAFF. However, B cell depletion would be desirable at least in some multiple sclerosis patients. The systemic induction of BAFF by IFN-beta therapy may facilitate the production of various autoantibodies and of IFN-neutralizing antibodies. Individual MS/NMO patients who have major B cell involvement may benefit less than others from IFN-beta therapy, thus explaining interindividual differences of the therapeutic response.


Asunto(s)
Factor Activador de Células B/metabolismo , Linfocitos B/efectos de los fármacos , Inmunoterapia/métodos , Interferón beta/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Adulto , Autoinmunidad , Factor Activador de Células B/sangre , Receptor del Factor Activador de Células B/metabolismo , Linfocitos B/inmunología , Estudios de Casos y Controles , Células Cultivadas , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Interferón beta/análisis , Masculino , Esclerosis Múltiple/inmunología , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo
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