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3.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 41(4): 223-230, jul. - ago. 2022. ilus, graf, tab
Artículo en Español | IBECS | ID: ibc-205184

RESUMEN

Objetivo: Conocer el estado actual de la técnica de localización radioguiada de lesiones no palpables de mama con o sin indicación de biopsia selectiva de ganglio centinela —ROLL, SNOLL y semillas de 125I— mediante la realización de una encuesta nacional elaborada por el Grupo de Trabajo de Cirugía Radioguiada (GTCRG) de la Sociedad Española de Medicina Nuclear e Imagen Molecular (SEMNIM). Material y métodos: En octubre del 2020 se envió la encuesta, en formato digital, a los distintos servicios de Medicina Nuclear de nuestra geografía. Se dio un tiempo de respuesta de 2meses con prórroga de 15 días. Se ha obtenido el número de procedimientos ROLL/SNOLL de cada centro y la metodología utilizada, recogiendo importantes detalles técnicos. Además, se ha incluido un apartado específico sobre las semillas de 125I. Los resultados se volcaron de forma automática en una hoja de cálculo Excel 2007 para su posterior análisis con el mismo programa. Resultados: La encuesta fue contestada por 55 centros; 21 utilizan arpón mientras que los 34 restantes emplean distintas técnicas de cirugía radioguiada (CRG) para la localización de lesiones no palpables de mama, desglosando los resultados en 13apartados. La dosis de trazador habitualmente utilizada es de 111 MBq para la técnica ROLL y de 222 MBq para la técnica SNOLL, con un volumen de 0,2ml. El protocolo más habitual es el de 2días. El 26% de los centros que realiza CRG utiliza semillas de 125I tanto para la detección de lesiones mamarias como de ganglios sospechosos/patológicos, siendo el tiempo entre la implantación y la extirpación es de unos 3 días, con posterior control radiológico en la mayoría de los casos. Conclusión: La encuesta pone de manifiesto la relevancia de la cirugía radioguiada en el manejo de los pacientes con cáncer de mama en las diferentes etapas de la enfermedad, con disparidad en la implementación de las nuevas técnicas y herramientas (AU)


Objective: To know the current status of the technique of radioguided localisation of non-palpable breast lesions with or without indication for selective sentinel node biopsy -ROLL, SNOLL and 125I seeds- by conducting a national survey developed by the Working Group on Radioguided Surgery (GTCRG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methods: In October 2020, the form was sent in digital format to the different nuclear medicine services in Spain. A response time of 2months with an overtime of 15 days was given. The number of ROLL/SNOLL procedures in each centre and the methodology used were obtained, including important technical details. In addition, a specific section on 125I seeds was included. The results were automatically downloaded into an Excel 2007 spreadsheet for subsequent analysis with the same program. Results: The survey was answered by 55 centres; 21 use wire-guided localisation while the remaining 34 use different radioguided surgery techniques (RGS) for the localisation of non-palpable breast lesions, with the results itemized into thirteen sections. The commonly used tracer dose is 111 MBq for the ROLL technique and 222 MBq for the SNOLL technique, with a volume of 0.2ml. The most common protocol is the two-day protocol. 26% of centres performing CRG use 125I seeds for both breast lesion and suspicious/pathological node detection, with the time between implantation and removal being about 3 days, with subsequent radiological control in most cases. Conclusion: The survey shows the relevance of radioguided surgery in the management of breast cancer patients at different stages of the disease, with disparity in the implementation of new techniques and tools, which responds to the multiple healthcare realities of Nuclear Medicine services (AU)


Asunto(s)
Humanos , Femenino , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/diagnóstico , Medicina Nuclear , Biopsia del Ganglio Linfático Centinela , Cirugía Asistida por Computador , Encuestas de Atención de la Salud , Radioisótopos de Yodo , Imagen Molecular , Sociedades Médicas , España
4.
Artículo en Inglés | MEDLINE | ID: mdl-35668015

RESUMEN

OBJECTIVE: To know the current status of the technique of radioguided localisation of non-palpable breast lesions with or without indication for selective sentinel node biopsy -ROLL, SNOLL and 125I seeds- by conducting a national survey developed by the Working Group on Radioguided Surgery (GTCRG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). MATERIAL AND METHODS: In October 2020, the form was sent in digital format to the different nuclear medicine services in Spain. A response time of 2 months with an overtime of 15 days was given. The number of ROLL/SNOLL procedures in each centre and the methodology used were obtained, including important technical details. In addition, a specific section on 125I seeds was included. The results were automatically downloaded into an Excel 2007 spreadsheet for subsequent analysis with the same program. RESULTS: The survey was answered by 55 centres; 21 use wire-guided localisation while the remaining 34 use different radioguided surgery techniques (RGS) for the localisation of non-palpable breast lesions, with the results itemized into thirteen sections. The commonly used tracer dose is 111 MBq for the ROLL technique and 222 MBq for the SNOLL technique, with a volume of 0.2 ml. The most common protocol is the two-day protocol. 26% of centres performing CRG use 125I seeds for both breast lesion and suspicious/pathological node detection, with the time between implantation and removal being about 3 days, with subsequent radiological control in most cases. CONCLUSION: The survey shows the relevance of radioguided surgery in the management of breast cancer patients at different stages of the disease, with disparity in the implementation of new techniques and tools, which responds to the multiple healthcare realities of Nuclear Medicine services.


Asunto(s)
Neoplasias de la Mama , Medicina Nuclear , Biopsia del Ganglio Linfático Centinela , Cirugía Asistida por Computador , Neoplasias de la Mama/diagnóstico , Femenino , Humanos , Radioisótopos de Yodo , Imagen Molecular , Biopsia del Ganglio Linfático Centinela/métodos , Sociedades Médicas , España
8.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32830080

RESUMEN

Isolated limb perfusion (ILP) is a method for treating unresectable lesions of limbs in patients with melanoma or sarcoma by using high doses of tumor necrosis factor alpha and melphalan. These high doses can result in high systemic toxicity if there is a drug leak from the isolated circulation of the limb to the systemic. This makes it imperative to monitor the leakage rate (F[%]) during the infusion, currently performed with radiotracers. The objective of this work was to develop a leakage monitoring protocol as accurate as possible to ensure safe ILP. MATERIAL AND METHOD: We built a phantom with 3compartments (body, limb and precordial area) and a high sensitivity collimator fitted to a portable gammacamera. We simulate ILP with scheduled leaks every 10minutes from 1% to 9% (theorical F[%]). We mesured F(%) using 2equation: one is the proposed in the literature and another corrected by decay of the radioisotope. We test the optimal radiopharmaceutical doses to minimize the detector dead time error and compare F(%) mesured by both equations regarding the theoretical F(%). The leakage monitoring protocol was used in 17 ILP of 16 patients and an analysis of the recorded data was performed. RESULTS: We found significant differences between F(%) mesured using the first equation and theoretical F(%), obtaining results very adjusted to the theorical after applying the decay correction. CONCLUSIONS: The decay correction of the radioisotope is a simple manner to carry out the procedure more safely, reducing the error in the calculation of F(%).

9.
Aust Vet J ; 98(12): 610-615, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32935332

RESUMEN

Cryptococcus species are environmental yeasts, with a worldwide distribution and remarkable environmental adaptation. Although many species do not cause disease, C. neoformans and C. gattii are causative agents of cryptococcosis, a life threatening infection and a significant public health problem worldwide. Infection especially affects immunocompromised animals and humans. In wildlife, cryptococcosis appears to be more prevalent in captive populations. The objective of this study was to assess whether apparently healthy quokkas (Setonix brachyurus) harbor Cryptococcus spp. Using cultural and molecular methods, we studied yeasts isolated from nasal swabs collected from 130 free-ranging quokkas on Rottnest Island (RI, n = 97) and the mainland (n = 33) of Western Australia. Unspeciated Cryptococcus spp. (from four quokkas), C. neoformans var. grubii (serotype A) (two quokkas) and C. magnus (one quokka) were isolated from the nasal lining of apparently healthy quokkas from RI. Cryptococcus neoformans var. grubii was isolated from animals captured in a human-populated area on RI. There was no significant effect of the presence of Cryptococcus on the results of haematology, blood chemistry, peripheral blood cell morphology or clinical examination. To the best of our knowledge, this is the first documented isolation of C. neoformans var. grubii (serotype A) and C. magnus in a free-ranging macropod in Western Australia. The public health implications of this finding should be further explored.


Asunto(s)
Cryptococcus neoformans , Animales , Humanos , Macropodidae , Nariz , Serogrupo , Australia Occidental
10.
J Endocrinol ; 244(2): 415-429, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32395971

RESUMEN

Among all the hormone-secreting pituitary tumours, prolactinomas are the most frequently found in the clinic. Since dopamine is the primary inhibitor of lactotroph function, dopamine agonists represent the first-line therapy. However, a subset of patients exhibits resistance to these drugs, and therefore, alternative treatments are desired. As activins inhibit prolactin gene expression through the inhibition of Pit-1 involving the p38MAPK pathway, in the present work, we studied the local activin system as an alternative inhibitory system for lactotroph hyperplasia treatment. We used two different mouse models of prolactinoma: transgenic mice with overexpression of the human chorionic gonadotropin ß-subunit (hCGß) and mice lacking dopamine receptor type 2. In both models, females, but not males, develop lactotroph hyperplasia from the fourth month of life. We found reduced expression of pituitary activin subunits and activin receptors in hyperplastic pituitaries from both models compared with wild-type counterparts. Consequently, hyperplastic pituitaries presented a reduced activin-inhibitory action on prolactin secretion. Additionally, while female wild-type lactotrophs presented high levels of phospho-p38MAPK, it was lost in prolactinomas, concomitant with decreased activin expression, increased Pit-1 expression and tumour development. In contrast, male pituitaries express higher mRNA levels of activin subunits ßA and ßB, which would suggest a stronger activin inhibitory function on lactotrophs, protecting this sex from tumour development, despite genotype. The present results highlight the importance of the activin inhibitory action on lactotroph function and place the local activin system as a new target for the treatment of dopamine agonist-resistant prolactinomas.


Asunto(s)
Activinas/metabolismo , Lactotrofos/metabolismo , Neoplasias Hipofisarias/genética , Prolactinoma/genética , Animales , Agonistas de Dopamina/farmacología , Resistencia a Antineoplásicos/genética , Femenino , Genotipo , Sistema de Señalización de MAP Quinasas/genética , Masculino , Ratones , Ratones Transgénicos , Hipófisis/metabolismo , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/tratamiento farmacológico , Prolactinoma/complicaciones , Prolactinoma/tratamiento farmacológico , ARN Mensajero/metabolismo , Factores Sexuales , Factor de Transcripción Pit-1/metabolismo
14.
J Mol Model ; 24(9): 244, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30128714

RESUMEN

An effectiveway of enhancing hydrogen storage on adsorbent materials can be induced by the hydrogen spill-over mechanism, although to date there is no general consensus which satisfactorily explains the mechanism. In this work, a possible reaction path to explain hydrogen adsorption is shown. Density-functional calculations were used to study the dissociation of molecular hydrogen near to a stressed region, as a consequence of chemisorbed hydrogen at the graphene-nitrogen surface. We found that as a result of the buckling induced by the chemisorbed hydrogen, the dissociation barrier of molecular hydrogen diminished by 0.84 eV. The chemisorbed hydrogen is the final state in the spill-over mechanism on a graphene-nitrogen decorated with palladium clusters. This effect helps to create hydrogen nanoislands that may change the diffusion and detrapping of H. An electronic structure analysis suggests that these systems occasionally present metallic or semiconductor behavior. Graphical Abstract Hydrogen dissociation and adsorption process via buckling defect.

15.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29941339

RESUMEN

BACKGROUND AND OBJECTIVE: Sentinel lymph node biopsy (SLNB) was created to reduce the morbidity associated with pelvic lymphadenectomy in the early stages of cervical cancer (CC), preserving its prognostic information. The goal is to assess the diagnostic validity of SLNB in CC in initial stages (IA1 with lymphovascular infiltration (LVI) +, IA2, IB1 and IIA1), thus avoiding unnecessary lymphadenectomies in many of the cases. MATERIAL AND METHOD: From January 2012 to April 2017, 23 patients with initial stages of CC were included in a cross-sectional study to evaluate the effectiveness of the SLNB in CC with a mixed technique of cervical injection of 99mTc-nanocolloid of albumin and methylene blue, using combined planar lymphoscintigraphy with multimodality SPECT/CT image and subsequent removal of the sentinel node (SN) by laparoscopy. RESULTS: The detection rate of SLNB with the mixed technique was 95.65%, with a negative predictive value (NPV) of 95.45% and sensitivity (S) of 100% in the case of bilateral drainage. The mean of excised SN was 3 (range 1-5). The bilateral detection rate in laparoscopy was 85.35%. The concordance between SPECT/CT and laparoscopy for the number and bilaterality of the SN using the Pearson coefficient was r = 0.727 and r = 0.833, respectively; p = 0.01. We only found one SN with a deferred result of micrometástasis and one false negative was detected. CONCLUSIONS: SLNB in CC using a mixed technique has a high detection and bilateral drainage rate, but S is still low if we include cases of unilateral drainage. A greater number of cases and the development of intraoperative ultrastaging could increase the S of the technique and to reduce the number of false negatives.


Asunto(s)
Biopsia del Ganglio Linfático Centinela , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/patología , Adulto , Estudios Transversales , Femenino , Humanos , Escisión del Ganglio Linfático , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias del Cuello Uterino/cirugía , Adulto Joven
16.
Rev Neurol ; 66(6): 175-181, 2018 Mar 16.
Artículo en Español, Inglés | MEDLINE | ID: mdl-29537056

RESUMEN

AIMS: To investigate whether or not the deficits in executive functions in the attention deficit hyperactivity disorder (ADHD) affect reading comprehension and identify a potential biological marker of this neuropsychological endophenotype through event-related potentials (ERP). The phenotypic association between reading comprehension and the specific functions of inhibition and working memory is studied. SUBJECTS AND METHODS: The sample consisted of 52 children with ADHD (8-13 years) divided in two groups according to the presence (TDAH-; n = 27; percentile < 30) or the absence (TDAH+; n = 25; percentile > 50) of reading comprehension deficits and a control group (n = 27). The executive functions were evaluated. The ERPs were assessed during a task in which anaphoric sentences of different lengths were presented, recording the ERP in the last adjective of the sentence that required a gender agreement. RESULTS: Working memory and inhibition were associated to reading comprehension performance. The ADHD+ group and the control group seem to detect the disagreement at 100 ms, while the ADHD- group does not activate its working memory until 250 ms. CONCLUSIONS: The delay in the implementation of the working memory mechanisms helps us to understand the deficits in reading comprehension of the ADHD- group.


TITLE: Correlatos electrofisiologicos de la lectura en niños con trastorno por deficit de atencion/hiperactividad.Objetivos. Investigar si los deficits en las funciones ejecutivas en el trastorno por deficit de atencion/hiperactividad (TDAH) afectan a su compresion lectora e identificar un potencial marcador biologico de este endofenotipo neuropsicologico a traves de potenciales relacionados con eventos. Especificamente, hipotetizar si las diferencias en memoria de trabajo e inhibicion mantienen una asociacion fenotipica con la comprension lectora en el TDAH. Sujetos y metodos. La muestra estuvo constituida por 52 niños con TDAH (8-13 años) divididos en dos grupos segun la presencia (TDAH­; n = 27; percentil < 30) o ausencia (TDAH+; n = 25; percentil > 50) de deficit en compresion lectora y un grupo control (n = 27). Se evaluaron las funciones ejecutivas y se realizo un experimento de potenciales relacionados con eventos en el que se presentaron oraciones anaforicas de diferentes longitudes, y se registraron los potenciales relacionados con eventos en el ultimo adjetivo de la oracion que requiere acuerdo de genero. Resultados. Se encontro una relacion entre memoria de trabajo e inhibicion con el rendimiento en compresion lectora. Mientras que los grupos de TDAH+ y control mostraron signos de deteccion de no concordancia sintactica a los 100 ms, el grupo de TDAH­ no activo la memoria de trabajo hasta los 250 ms. Conclusiones. La lentitud en la puesta en marcha de los mecanismos de memoria de trabajo nos ayuda a entender los deficits en comprension lectora del grupo de TDAH­.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Dislexia/fisiopatología , Potenciales Evocados , Memoria a Corto Plazo/fisiología , Lectura , Adolescente , Niño , Comprensión , Electroencefalografía , Electrooculografía , Femenino , Humanos , Masculino , Psicología Infantil
17.
Phys Chem Chem Phys ; 18(48): 33158-33170, 2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27892574

RESUMEN

The hydrogen spill-over mechanism was studied by applying Density Functional Theory. We used small palladium clusters to act as the catalyst supported on the substrate (comprised of pyridinic and pyrrolic nitrogen doped graphene), in order to study hydrogen dissociation, migration and diffusion. Charge transfer and strong binding between the catalyst and the substrate lead to dissociated states of H2 and prevent clusters from detaching and coalescing. In dissociated cases of H2 on Pd clusters, energy barriers below 0.6 eV were found. Likewise, concerning hydrogen migration from the catalyst to the substrate, energy barrier values of 0.8 eV (pyridinic defect) and 0.5 eV (pyrrolic defect) were apparent in the case of the Pd4 cluster at full hydrogen saturation. This indicates that hydrogen dissociation and migration may occur spontaneously at room temperature. This result shows that the interaction between the defects and the small metal clusters may explain the role that defects play in hydrogen migration from the catalyst to the substrate. Subsequently, it was found that thermal desorption does not limit chemisorbed hydrogen diffusion on the substrate. This work may thus help to determine experimental strategies with the capacity to enhance hydrogen storage.

18.
Rev Esp Med Nucl Imagen Mol ; 35(3): 193-6, 2016.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26750553

RESUMEN

The Erdheim-Chester disease (ECD) is an extremely rare form of non-Langerhans cell histiocytosis. The main difficulty for its diagnosis lies in the wide variety of non-specific symptoms and signs that can occur in the disease process, leading, therefore, to there being no clear-cut algorithm as a guide for an optimal biopsy to confirm the diagnosis. An 81-year-old male with history of diabetes insipidus was admitted due to non-specific respiratory signs. Imaging techniques revealed osteoblastic lesions in the lumbar spine. Whole-body bone-scintigraphy (BS) was performed, in which lesions involving the axial and appendicular skeleton, with different rates of osteoblastic activity, were observed. This highlighted a symmetrical severely intense uptake in the knees, leading to an accurate biopsy specimen that enabled making the definitive diagnosis. BS is a widely available, safe, and inexpensive technique that shows a characteristic pattern of uptake for ECD, thus its use is highly recommended for screening and guiding biopsy if clinical suspicion exists. Furthermore, when the scintigraphy pattern is incidentally observed, biopsy of increased uptake areas (tibia preferably) is mandatory in order to rule out the disease.


Asunto(s)
Huesos/diagnóstico por imagen , Enfermedad de Erdheim-Chester/diagnóstico por imagen , Anciano de 80 o más Años , Biopsia , Huesos/patología , Enfermedad de Erdheim-Chester/patología , Histiocitosis de Células no Langerhans , Humanos , Masculino , Tibia/diagnóstico por imagen
19.
Rev. esp. med. nucl. (Ed. impr.) ; 30(6): 365-367, nov.-dic. 2011.
Artículo en Español | IBECS | ID: ibc-91479

RESUMEN

El síndrome de neoplasia endocrina múltiple 2B (MEN 2B) es una entidad poco frecuente, que se caracteriza por la presencia de carcinoma medular de tiroides (CMT) en un 100% de los casos. El fenotipo de este síndrome incluye rasgos marfanoides y neuromas mucocutáneos. Describimos el caso de un paciente con un síndrome MEN 2B, al que se le diagnostica un cáncer medular de tiroides a partir del hallazgo de metástasis pulmonares y analizamos el papel del DMSA-V y de los nuevos sistemas híbridos SPECT-TAC en el estudio de extensión y seguimiento del CMT(AU)


Multiple endocrine neoplasia syndrome, type 2B (MEN 2B), is a rare entity characterized by the presence of medullary thyroid cancer in 100% of the cases. The phenotype of this syndrome consists in the presence of marfanoid features and mucocutaneous neuromas. We describe the case of a male patient with MEN 2B syndrome who was diagnosed with medullary thyroid cancer after lung metastases was found. We analyze the role of DMSA-V and the new hybrid SPECT-CT scan systems in the extension study and monitoring of medullary thyroid cancer(AU)


Asunto(s)
Humanos , Masculino , Adulto , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Exametazima de Tecnecio Tc 99m , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Neoplasias de la Tiroides , Tiroidectomía/métodos , Tiroidectomía , Octreótido/uso terapéutico , Tomografía Computarizada de Emisión de Fotón Único/tendencias , Tomografía Computarizada de Emisión de Fotón Único , Ácido Dimercaptosuccínico de Tecnecio Tc 99m/metabolismo , Ácido Dimercaptosuccínico de Tecnecio Tc 99m/farmacocinética , Neoplasia Endocrina Múltiple Tipo 2a/complicaciones , Neoplasia Endocrina Múltiple Tipo 2a/diagnóstico
20.
Rev Esp Med Nucl ; 30(6): 365-7, 2011.
Artículo en Español | MEDLINE | ID: mdl-21444129

RESUMEN

Multiple endocrine neoplasia syndrome, type 2B (MEN 2B), is a rare entity characterized by the presence of medullary thyroid cancer in 100% of the cases. The phenotype of this syndrome consists in the presence of marfanoid features and mucocutaneous neuromas. We describe the case of a male patient with MEN 2B syndrome who was diagnosed with medullary thyroid cancer after lung metastases was found. We analyze the role of DMSA-V and the new hybrid SPECT-CT scan systems in the extension study and monitoring of medullary thyroid cancer.


Asunto(s)
Carcinoma Medular/secundario , Vértebras Lumbares/diagnóstico por imagen , Imagen Multimodal , Neoplasia Endocrina Múltiple Tipo 2b/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos , Neoplasias de la Columna Vertebral/secundario , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Vértebras Torácicas/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Tomografía Computarizada por Rayos X , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencenosulfonatos/administración & dosificación , Carcinoma Medular/diagnóstico por imagen , Carcinoma Medular/tratamiento farmacológico , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/secundario , Masculino , Neoplasia Endocrina Múltiple Tipo 2b/genética , Disección del Cuello , Niacinamida/análogos & derivados , Octreótido/administración & dosificación , Compuestos de Fenilurea , Proteínas Proto-Oncogénicas c-ret/genética , Piridinas/administración & dosificación , Sorafenib , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/tratamiento farmacológico , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adulto Joven
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