Probing T1-T2 interactions and their imaging implications through a thermally responsive nanoprobe.

The complex and specialised diagnostic process through magnetic resonance imaging (MRI) could be simplified with the implementation of dual T1-T2 contrast agents. T1- and T2-weighted MR are compatible modalities, and co-acquisition of contrast enhanced images in both T1 and T2 will drastically reduce artefacts and provide double-checked results. To date, efforts in the development of dual MRI probes have provided inconsistent results. Here we present the preparation and relaxometric study of a dual T1-T2 MRI probe based on superparamagnetic nanoparticles, paramagnetic Gd3+ chelates and pNIPAM (poly(N-isopropylacrylamide)), in which the distance between paramagnetic and superparamagnetic species can be modulated externally via temperature variations. Such a probe alleviates traditional nanotechnology limitations (e.g. batch to batch variability) as comparisons can be established within a single probe.

Current status of prenatal diagnosis in Cuba: causes of low prevalence of Down syndrome.

OBJECTIVES: To analyze trends in cytogenetic prenatal diagnosis in Cuba and to analyze possible causes leading to a low Down syndrome prevalence in a country where the triple test is not available. METHODS: An analysis of the Cuban program in prenatal cytogenetic diagnosis from 1984 to 2012 was conducted. Results are described, with particular emphasis on indications, abnormal results, types of invasive procedures, and terminations of pregnancy. RESULTS: Cytogenetic prenatal diagnostic analyses (n = 75,095) were conducted; maternal age was the indication for 77.9% of the amniocenteses and chorionic villus samplings. The detection rate of chromosomally abnormal pregnancies was 2.3% for maternal age and increased to 8-9% for other indications. When a chromosomal abnormality was identified, 88.5% terminated the pregnancy. In 2002, the live birth prevalence of Down syndrome was 8.4 per 10,000 live births, and in 2012, 7 per 10,000. CONCLUSION: Prenatal diagnosis in Cuba has contributed to a significant reduction in chromosomal aberrations. The impact increased because of the demographic trends of the population, the high index of terminations of pregnancy, and the establishment of a network of cytogenetic laboratories throughout Cuba.

Novel hexanuclear copper(II) complex built from a simple tetrachelating triazole ligand: synthesis, structure, and magnetism.

A new easy symmetric 3,5-disubstituted 1,2,4-triazole ligand (H3diV) by reaction with an excess of copper(II) salt has afforded a novel hexanuclear compound (Cu/HdiV ratio of 6:2) through a bis(trans-cis-cis-trans) binding mode, exhibiting two types of Cu(II) centers and two clearly distinguishable antiferromagnetic J1 (-234 cm(-1)) and J2 (-35 cm(-1)) coupling constants.

Máculas hipopigmentadas focales / Focal Hypopigmented Macules

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Clínica y dermoscopia de la enfermedad de Bowen pigmentada / Clinical and Dermoscopic Features of Pigmented Bowen Disease

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Carcinoma basoescamoso mutilante en región facial / Facial mutilant basosquamous carcinoma

El carcinoma basoescamoso constituye una neoplasia epithelial maligna poco frecuente, que comparte características clínicas y biológicas con el carcinoma basocelular y espinocelular. Esta neoplasia ha sido considerada durante años una variedad de carcinoma basocelular, aunque en la actualidad se acepta plenamente su entidad propia. Presentamos el caso de un varón de 59 años de edad, indigente, que presentaba lesión tumoral ulcerada, de cuatro años de evolución, localizada en región malar izquierda, orbitaria y pirámide nasal, con importante destrucción de estas estructuras y extensión a la base del cráneo a través del nervio óptico. La importancia del carcinoma basoescamoso radica en su gran agresividad local, tendencia a la recidiva y capacidad de producir metástasis a distancia, por lo que el tratamiento más efectivo es la detección precoz y extirpación completa del mismo; hecho, que como ocurre en el caso que presentamos, no es siempre posible

Basosquamous carcinoma is a rare epithelial malignant neoplasm with clinical and biological features of both basal and squamous cell carcinoma. This neoplasm has been characterized for years as a variant of basal cell carcinoma, although now it is widely accepted as a clinical entity. We report a 59-year-old male patient, homeless, who presented an ulcerated tumoral lesion from four years ago, located in left malar region, orbit and nasal pyramid. It caused an important destruction of these anatomic structures and spred out the skull base through optic nerve. The most important features of basosquamous carcinoma are its great local aggressiveness, high frequency of recurrences and its metastatic potential. Because of that, the most effective therapeutic measure is the early detection and complete removement of these tumours; although, as the case we report, it is not always possible

[Allergic contact dermatitis to temporary henna tattoos]. / Dermatitis de contacto alérgica a tatuajes temporales de henna.

INTRODUCTION: In the last years there have been increasing reports of adverse cutaneous reactions to temporary black henna tattoos. Black henna does not exist naturally, it is obtained from original henna after the addition of other compounds, among them paraphenylenediamine (PPD), that darken it and facilitate the process of tattoing. Paraphenylenediamine is an aromatic compound that presents cross reactions with other components that have a benzene ring in their molecular structure. Many of these products may be present in the daily life of any person. MATERIAL AND METHODS: We reviewed patients that have shown erythema, inflammation and/or vesiculation in a previously tattooed area. The patients have undergone a temporary tattoo in street stalls during the summer period (2004-2005). A total of five patients were included, there were four men and one woman with a mean age of 13 years (3-34) and a mean latency period of 9.4 days (5-14). Black ink and plastic stencils were used to perform the tattoo. None of the patients has had previous contact with hair dyes or tattoos and none of them referred a personal history of atopic dermatitis. Patch testing was carried out using the standard set of the Spanish Group for Research in Contact Dermatitis [GEIDC] (TRUE TEST, Pharmacia. Hillerod. Denmark), with readings at 48 and 96 hours. RESULTS: Sensitization to PPD is confirmed in three patients, one of them was also sensitized to formaldehyde. Hypopigmented scars persist in three patients. CONCLUSIONS: Black henna pseudotattoos are a source of sensitization to PPD with potential severe consequences in a medium to long term. Currently there is no specific legislation with respect to the practice of this type of tattoos in our country.

Dermatitis de contacto alérgica a tatuajes temporales de henna / Allergic contact dermatitis to temporary henna tattoos

Introducción. Las comunicaciones de reacciones cutáneas adversas a tatuajes temporales por henna negra son cada vez más frecuentes en los últimos años. La henna negra no existe de forma natural; se obtiene a partir de la henna original añadiéndole otros compuestos que la oscurecen y facilitan el proceso de tatuaje, entre ellos la parafenilendiamina (PPD). La PPD es un compuesto aromático que presenta reacciones cruzadas con otros componentes con anillo bencénico en su estructura molecular. Muchos de estos productos pueden estar presentes en la vida cotidiana de cualquier persona. Material y métodos. Realizamos una revisión de pacientes que presentaran un cuadro de eritema, inflamación y/o vesiculación en la zona tatuada previamente. Los pacientes se habían realizado un tatuaje temporal en puestos callejeros durante el periodo estival (2004-2005). Se incluyeron un total de 5 pacientes, 4 varones/1 mujer, con una edad media de 13 años (3-34 años) y un periodo de latencia medio de 9,4 días (5-14 días). Para el tatuado usaron tinta de color negro y plantillas de material plástico. Ninguno de los pacientes había tenido contacto previo con tintes capilares ni tatuajes y tampoco refirieron antecedentes personales de dermatitis atópica. Se realizaron pruebas epicutáneas con la batería estándar del GEIDC (TRUE TEST® Pharmacia. Hillerod. Denmark), con lectura a las 48 y 96 horas. Resultados. Se confirma una sensibilización a la PPD en 3 pacientes, en uno de ellos también a formaldehído. En 3 pacientes persisten las cicatrices hipopigmentadas. Conclusiones. Los pseudotatuajes con henna negra son una fuente de sensibilización a PPD con consecuencias graves potenciales a medio-largo plazo. En la actualidad no existe ninguna ley que regule la práctica de este tipo de tatuajes en nuestro país (AU)

Introduction. In the last years there have been increasing reports of adverse cutaneous reactions to temporary black henna tattoos. Black henna does not exist naturally, it is obtained from original henna after the addition of other compounds, among them paraphenilendiamine (PPD), that darken it and facilitate the process of tattoing. Paraphenilendiamine is an aromatic compound that presents cross reactions with other components that have a benzene ring in their molecular structure. Many of these products may be present in the daily life of any person. Material and methods. We reviewed patients that have shown erythema, inflammation and/or vesiculation in a previously tattooed area. The patients have undergone a temporary tattoo in street stalls during the summer period (2004-2005). A total of five patients were included, there were four men and one woman with a mean age of 13 years (3-34) and a mean latency period of 9.4 days (5-14). Black ink and plastic stencils were used to perform the tattoo. None of the patients has had previous contact with hair dyes or tattoos and none of them referred a personal history of atopic dermatitis. Patch testing was carried out using the standard set of the Spanish Group for Research in Contact Dermatitis [GEIDC] (TRUE TEST ®, Pharmacia. Hillerod. Denmark), with readings at 48 and 96 hours. Results. Sensitization to PPD is confirmed in three patients, one of them was also sensitized to formaldehyde. Hypopigmented scars persist in three patients. Conclusions. Black henna pseudotattoos are a source of sensitization to PPD with potential severe consequences in a medium to long term. Currently there is no specific legislation with respect to the practice of this type of tattoos in our country (AU)

[Facial mutilant basosquamous carcinoma]. / Carcinoma basoescamoso mutilante en región facial.

Basosquamous carcinoma is a rare epithelial malignant neoplasm with clinical and biological features of both basal and squamous cell carcinoma. This neoplasm has been characterized for years as a variant of basal cell carcinoma, although now it is widely accepted as a clinical entity. We report a 59-year-old male patient, homeless, who presented an ulcerated tumoral lesion from four years ago, located in left malar region, orbit and nasal pyramid. It caused an important destruction of these anatomic structures and spred out the skull base through optic nerve. The most important features of basosquamous carcinoma are its great local aggressiveness, high frequency of recurrences and its metastatic potential. Because of that, the most effective therapeutic measure is the early detection and complete removement of these tumours; although, as the case we report, it is not always possible.