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1.
Eur J Nucl Med Mol Imaging ; 45(2): 235-242, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29075832

RESUMEN

OBJECTIVE: To evaluate the diagnostic performance of [68Ga]Ga-PSMAHBED-CC conjugate 11 positron emission tomography (PSMA-PET) in the early detection of metastases in patients with biochemical recurrence (BCR) after radical prostatectomy (RP) for clinically non-metastatic prostate cancer, to compare it to CT/MRI alone and to assess its impact on further therapeutic decisions. MATERIAL AND METHODS: We retrospectively assessed 117 consecutive hormone-naïve BCR patients who had 68Ga-PSMA 11 PET/CT (n = 46) or PET/MRI (n = 71) between May 2014 and January 2017. BCR was defined as two PSA rises above 0.2 ng/ml. Two dedicated uro-oncological imaging experts (radiology/nuclear medicine) reviewed separately all images. All results were presented in a blinded sequential fashion to a multidisciplinary tumorboard in order to assess the influence of PSMA-PET imaging on decision-making. RESULTS: The median time from RP to BCR was 36 months (IQR 16-72). Overall, 69 (59%) patients received postoperative radiotherapy. Median PSA level at the time of imaging was 1.04 ng/ml (IQR 0.58-1.87). PSMA-positive lesions were detected in 100 (85.5%) patients. Detection rates were 65% for a PSA value of 0.2 to <0.5 ng/ml, 85.7% for 0.5 to <1, 85.7% for 1 to <2 and 100% for ≥2. PSMA-positive lesions could be confirmed by either histology (16%), PSA decrease in metastasis-directed radiotherapy (45%) or additional information in diffusion-weighted imaging when PET/MRI was performed (18%) in 79% of patients. PSMA-PET detected lesions in 67 patients (57.3%) who had no suspicious correlates according to the RECIST 1.1 criteria on MRI or CT. PSMA-PET changed therapeutic decisions in 74.6% of these 67 patients (p < 0.001), with 86% of them being considered for metastases-directed therapies. CONCLUSIONS: We confirm the high performance of PSMA-PET imaging for the detection of disease recurrence sites in patients with BCR after RP, even at relatively low PSA levels. Moreover, it adds significant information to standard CT/MRI, changing treatment strategies in a significant number of patients.


Asunto(s)
Toma de Decisiones , Ácido Edético/análogos & derivados , Oligopéptidos/metabolismo , Tomografía de Emisión de Positrones , Prostatectomía , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/metabolismo , Anciano , Ácido Edético/metabolismo , Isótopos de Galio , Radioisótopos de Galio , Humanos , Ligandos , Masculino , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Recurrencia , Estudios Retrospectivos
2.
Nat Genet ; 23(1): 71-5, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471502

RESUMEN

In most mammals the pancreas develops from the foregut endoderm as ventral and dorsal buds. These buds fuse and develop into a complex organ composed of endocrine, exocrine and ductal components. This developmental process depends upon an integrated network of transcription factors. Gene targeting experiments have revealed critical roles for Pdx1, Isl1, Pax4, Pax6 and Nkx2-2 (refs 3,4,5,6,7, 8,9,10). The homeobox gene HLXB9 (encoding HB9) is prominently expressed in adult human pancreas, although its role in pancreas development and function is unknown. To facilitate its study, we isolated the mouse HLXB9 orthologue, Hlxb9. During mouse development, the dorsal and ventral pancreatic buds and mature beta-cells in the islets of Langerhans express Hlxb9. In mice homologous for a null mutation of Hlxb9, the dorsal lobe of the pancreas fails to develop. The remnant Hlxb9-/- pancreas has small islets of Langerhans with reduced numbers of insulin-producing beta-cells. Hlxb9-/- beta-cells express low levels of the glucose transporter Glut2 and homeodomain factor Nkx 6-1. Thus, Hlxb9 is key to normal pancreas development and function.


Asunto(s)
Proteínas de Homeodominio/genética , Islotes Pancreáticos/anomalías , Proteínas del Tejido Nervioso , Páncreas/anomalías , Factores de Transcripción/genética , Animales , Proteínas de Unión al ADN/metabolismo , Proteínas del Ojo , Factores de Transcripción Forkhead , Genotipo , Glucagón/metabolismo , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio/metabolismo , Humanos , Inmunohistoquímica , Insulina/metabolismo , Islotes Pancreáticos/embriología , Islotes Pancreáticos/metabolismo , Proteínas con Homeodominio LIM , Ratones , Modelos Genéticos , Datos de Secuencia Molecular , Neuronas Motoras/metabolismo , Proteínas Nucleares , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box , Páncreas/embriología , Páncreas/metabolismo , Polipéptido Pancreático/metabolismo , Proteínas Represoras , Somatostatina/metabolismo , Factores de Tiempo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Pez Cebra
3.
Hautarzt ; 64(5): 332-3, 2013 May.
Artículo en Alemán | MEDLINE | ID: mdl-23535947

RESUMEN

The basal cell carcinoma is a malignant tumor which originates from the epidermal stem cells. The polypoid basal cell carcinoma is an uncommon variant. We report on a 70-year-old man with a red nodule on his left breast. Clinical and histopathologic criteria led to the diagnosis of polypoid basal cell carcinoma. This variant is characterized by exophytic, polypoid growth. Histologically, the aggregates of tumor cells are usually limited to the polypoid zone.


Asunto(s)
Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama Masculina/cirugía , Carcinoma Basocelular/patología , Carcinoma Basocelular/cirugía , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Anciano , Diagnóstico Diferencial , Humanos , Masculino
4.
Hautarzt ; 63(12): 920-3, 2012 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-23111567

RESUMEN

Mycosis fungoides (MF) is a low-grade cutaneous T-cell lymphoma characterized by skin-homing CD4- positive helper T cells. Mycosis fungoides palmaris et plantaris is an uncommon variant primarily involving the palms and soles. An 80-year old man presented with hyperkeratotic erythematous palmoplantar changes. Clinical and histopathologic criteria led to the diagnosis mycosis fungoides palmaris et plantaris. Tumor staging using sonography of the abdomen and lymph nodes, chest x-ray and blood examination is recommended, because extracutaneous manifestations may be present.


Asunto(s)
Complejo CD3/análisis , Dermatosis del Pie/diagnóstico , Dermatosis de la Mano/diagnóstico , Micosis Fungoide/diagnóstico , Neoplasias Cutáneas/diagnóstico , Linfocitos T/patología , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/uso terapéutico , Biopsia , Linfocitos T CD8-positivos/patología , Quimioterapia Adyuvante , Terapia Combinada , Diagnóstico Diferencial , Electrones/uso terapéutico , Dermatosis del Pie/patología , Dermatosis del Pie/radioterapia , Dermatosis de la Mano/patología , Dermatosis de la Mano/radioterapia , Humanos , Metástasis Linfática/patología , Masculino , Metotrexato/uso terapéutico , Micosis Fungoide/tratamiento farmacológico , Micosis Fungoide/patología , Micosis Fungoide/radioterapia , Piel/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/radioterapia
5.
Hautarzt ; 62(5): 324-7, 2011 May.
Artículo en Alemán | MEDLINE | ID: mdl-21437703

RESUMEN

Cylindromatosis describes a rare autosomal dominantly inherited disease characterized by multiple cylindromas, which are located on the scalp and the neck. We report on an 80-year-old patient with a long history of multiple asymptomatic, skin-colored tumors on head, neck and upper part of the body. Clinical and histopathologic criteria lead to the diagnosis of cylindromatosis. Development of cylindrocarcinoma has been reported, so one must choose on an individual basis between close follow-up and prophylactic excision.


Asunto(s)
Carcinoma Adenoide Quístico/patología , Carcinoma Adenoide Quístico/cirugía , Carcinoma de Apéndice Cutáneo/patología , Carcinoma de Apéndice Cutáneo/cirugía , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Síndromes Neoplásicos Hereditarios/patología , Síndromes Neoplásicos Hereditarios/cirugía , Anciano de 80 o más Años , Humanos , Masculino , Neoplasias Cutáneas , Resultado del Tratamiento
6.
Neuroimage Clin ; 32: 102813, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34544031

RESUMEN

An elemental function of brain dopamine is to coordinate cognitive and motor resources for successful exploitation of environmental energy sources. Dopamine transmission, goal-directed behavior, and glucose homeostasis are altered in schizophrenia patients prior to and after initiation of pharmacological treatment. Thus, we investigated the relationship between blood glucose levels and brain dopamine signaling in drug-naïve patients with first-episode psychosis. We quantified blood glucose levels and binding of the dopamine D2/3 receptor agonist radioligand (+)-[11C]-PHNO in 15 medication-naïve patients and 27 healthy volunteers employing positron emission tomography. Whole-brain voxel-wise linear model analysis identified two clusters of significant interaction between blood glucose levels and diagnosis on (+)-[11C]-PHNO binding-potential values. We observed positive relationships between blood glucose levels and binding-potential values in healthy volunteers but negative ones in patients with first episode psychosis in a cluster surviving rigorous multiple testing correction located in the in the right ventral tegmental area. Another cluster of homologous behavior, however at a lower level of statistical significance, comprised the ventral striatum and pallidum. Extracellular dopamine levels are a major determinant of (+)-[11C]-PHNO binding in the brain. In line with the concept that increased dopamine signaling occurs when goal-directed behavior is needed for restoring energy supply, our data indicate that in healthy volunteers, extracellular dopamine levels are high when blood glucose levels are low and vice-versa. This relationship is reversed in patients with first-episode psychosis, possibly reflecting an underlying pathogenic alteration that links two seemingly unrelated aspects of the illness: altered dopamine signaling and dysfunctional glucose homeostasis.


Asunto(s)
Dopamina , Esquizofrenia , Glucemia , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Radioisótopos de Carbono , Agonistas de Dopamina , Humanos , Tomografía de Emisión de Positrones , Receptores de Dopamina D3/metabolismo , Esquizofrenia/diagnóstico por imagen , Tomografía Computarizada por Rayos X
7.
Rev Sci Instrum ; 91(4): 044101, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357721

RESUMEN

We have developed an electrochemical cell for in situ 2-Dimensional Surface Optical Reflectance (2D-SOR) studies during anodization and cyclic voltammetry. The 2D-SOR signal was recorded from electrodes made of polycrystalline Al, Au(111), and Pt(100) single crystals. The changes can be followed at a video rate acquisition frequency of 200 Hz and demonstrate a strong contrast between oxidizing and reducing conditions. Good correlation between the 2D-SOR signal and the anodization conditions or the cyclic voltammetry current is also observed. The power of this approach is discussed, with a focus on applications in various fields of electrochemistry. The combination of 2D-SOR with other techniques, as well as its spatial resolution and sensitivity, has also been discussed.

8.
Rev Sci Instrum ; 90(3): 033703, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30927778

RESUMEN

We have combined three techniques, High Energy Surface X-Ray Diffraction (HESXRD), Surface Optical Reflectance, and Planar Laser Induced Fluorescence in an operando study of CO oxidation over a Pd(100) catalyst. We show that these techniques provide useful new insights such as the ability to verify that the finite region being probed by techniques such as HESXRD is representative of the sample surface as a whole. The combination is also suitable to determine when changes in gas composition or surface structure and/or morphology occur and to subsequently correlate them with high temporal resolution. In the study, we confirm previous results which show that the Pd(100) surface reaches high activity before an oxide can be detected. Furthermore, we show that the single crystal catalyst surface does not behave homogeneously, which we attribute to the surface being exposed to inhomogeneous gas conditions in mass transfer limited scenarios.

9.
Neuron ; 23(4): 675-87, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10482235

RESUMEN

Sonic hedgehog (Shh) specifies the identity of both motor neurons (MNs) and interneurons with morphogen-like activity. Here, we present evidence that the homeodomain factor HB9 is critical for distinguishing MN and interneuron identity in the mouse. Presumptive MN progenitors and postmitotic MNs express HB9, whereas interneurons never express this factor. This pattern resembles a composite of the avian homologs MNR2 and HB9. In mice lacking Hb9, the genetic profile of MNs is significantly altered, particularly by upregulation of Chx10, a gene normally restricted to a class of ventral interneurons. This aberrant gene expression is accompanied by topological disorganization of motor columns, loss of the phrenic and abducens nerves, and intercostal nerve pathfinding defects. Thus, MNs actively suppress interneuron genetic programs to establish their identity.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Genes Homeobox/genética , Proteínas Hedgehog/fisiología , Proteínas de Homeodominio/biosíntesis , Interneuronas/fisiología , Neuronas Motoras/fisiología , Factores de Transcripción/biosíntesis , Proteínas de Xenopus , Animales , Axones/fisiología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Embrión de Pollo , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas de Homeodominio/genética , Inmunohistoquímica , Hibridación in Situ , Ratones , Ratones Transgénicos , Mitosis/fisiología , Proteínas Represoras/genética , Células Madre/fisiología , Factores de Transcripción/genética , Xenopus laevis/fisiología
10.
Nat Neurosci ; 4 Suppl: 1183-91, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11687828

RESUMEN

The spinal cord is composed of anatomically distinct classes of neurons that perform sensory and motor functions. Because of its relative simplicity, the spinal cord has served as an important system for defining molecular mechanisms that contribute to the assembly of circuits in the central nervous system. At early embryonic stages, the neural tube contains multipotential cells whose identity becomes specified by cell-to-cell signaling. This review will focus on the progress made in understanding the transcriptional networks that become activated by these cell-cell interactions, with particular emphasis on the neurons that contribute to locomotor control. Remarkably, many of the transcription factors implicated in neuronal specification in the spinal cord are found to inhibit transcription, which has led to a 'derepression' model for cell fate specification in the developing spinal cord.


Asunto(s)
Diferenciación Celular/genética , Regulación del Desarrollo de la Expresión Génica/genética , Neuronas/citología , Médula Espinal/embriología , Células Madre/citología , Factores de Transcripción/genética , Animales , Humanos , Modelos Biológicos , Neuronas/metabolismo , Proteínas Represoras/genética , Médula Espinal/citología , Médula Espinal/metabolismo , Células Madre/metabolismo
11.
Mol Cell Biol ; 18(7): 3811-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9632765

RESUMEN

The Xenopus TFIIIA gene is transcribed very efficiently in oocytes. In addition to a TATA element at -30, we show that from -425 to +7 the TFIIIA gene contains only two positive cis elements centered at -267 (element 1) and -230 (element 2). This arrangement of the cis elements in the TFIIIA gene is striking because these two elements are positioned very close to each other yet separated from the TATA element by approximately 190 nucleotides. We show that the 190-nucleotide spacing between the TATA element and the upstream cis elements (elements 1 and 2) is critical for efficient transcription of the gene in oocytes and that a nucleosome is positioned in this intervening region. This nucleosome may act positively on TFIIIA transcription in oocytes by placing transcription factors bound at elements 1 and 2 in a favorable position relative to the transcription complex at the TATA element.


Asunto(s)
Cromatina/fisiología , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/genética , Transcripción Genética , Animales , Secuencia de Bases , Cromatina/química , Mapeo Cromosómico , ADN , Regulación de la Expresión Génica , Datos de Secuencia Molecular , Oocitos , Factor de Transcripción TFIIA , Xenopus
12.
Curr Opin Neurobiol ; 8(1): 27-36, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9568389

RESUMEN

Recent progress has been made in defining the developmental mechanisms that contribute to the diversification of motor neuron subtypes, which differ in transcription factor gene expression and synaptic connections. These studies suggest that progenitor cells acquire specific motor neuron identities through the coordinate actions of multiple factors. Current evidence suggests that Sonic hedgehog initiates a common pathway for motor neuron differentiation, while positionally distributed factors act to assign subtype identities.


Asunto(s)
Neuronas Motoras/fisiología , Sistema Nervioso/crecimiento & desarrollo , Neuronas/fisiología , Animales , Femenino , Regulación del Desarrollo de la Expresión Génica/fisiología , Humanos , Sistema Nervioso/embriología , Embarazo
13.
Curr Opin Neurobiol ; 10(1): 72-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10679434

RESUMEN

Considerable progress has been made in understanding how combinatorially expressed transcription factors control the development of neuronal subtypes in the fly and vertebrate central nervous systems. The mode of action of many of these factors has been conserved from invertebrates to vertebrates throughout evolution, such as the formation and regulation of specific transcriptional complexes, the utilization of repressors for maintaining specificity, and the use of phosphorylation as an important means for transiently altering transcriptional activity.


Asunto(s)
Sistema Nervioso Central/embriología , Regulación del Desarrollo de la Expresión Génica/genética , Neuronas Motoras/metabolismo , Neuronas Motoras/fisiología , Transcripción Genética/genética , Animales , Tipificación del Cuerpo/genética , Sistema Nervioso Central/citología , Sistema Nervioso Central/metabolismo , Drosophila melanogaster , Genes Homeobox/genética , Genes Homeobox/fisiología , Fosforilación , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Tiempo
14.
Vision Res ; 40(16): 2177-86, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10878279

RESUMEN

Perceptual multistability refers to cases where perception alternates between two or more interpretations of an unchanging sensory stimulus. In a first experiment we trained eight pigeons to discriminate horizontal and vertical apparent motion stimuli and then presented a multistable display. In five cases their behavior showed alternations similar to human experiments. In a second experiment we varied the aspect ratio of the display in order to support the hypothesis of a percept-driven nature of the switching behavior. The pecking rates and mean phase durations varied as predicted. This is the first evidence of visual multistability in animals confronted with classical ambiguous figures. The data suggest a stochastic mechanism.


Asunto(s)
Columbidae/fisiología , Percepción de Movimiento/fisiología , Adaptación Fisiológica , Animales , Procesos Estocásticos
20.
AORN J ; 48(2): 178, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3421685
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