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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.
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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.
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Síndrome de Down/diagnóstico , Síndrome de Down/epidemiologia , Diagnóstico Pré-Natal/estatística & dados numéricos , Adulto , Amniocentese/estatística & dados numéricos , Amostra da Vilosidade Coriônica/estatística & dados numéricos , Estudos Transversais , Cuba/epidemiologia , Análise Citogenética/estatística & dados numéricos , Feminino , Humanos , Idade Materna , Gravidez , Prevalência , Sistema de Registros , Adulto JovemRESUMO
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.
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Cobre/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Triazóis/química , Ligantes , Fenômenos Magnéticos , Modelos Moleculares , Estrutura Molecular , TemperaturaRESUMO
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.
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Dermatite Alérgica de Contato/etiologia , Naftoquinonas , Fenilenodiaminas/efeitos adversos , Tatuagem/efeitos adversos , Adulto , Benzoquinonas/efeitos adversos , Benzoquinonas/farmacocinética , Biotransformação , Criança , Pré-Escolar , Feminino , Humanos , Hipopigmentação/etiologia , Tinta , Masculino , Testes do Emplastro , Fenilenodiaminas/administração & dosagem , Fenilenodiaminas/farmacocinética , Pró-Fármacos/administração & dosagem , Pró-Fármacos/efeitos adversos , Pró-Fármacos/farmacocinéticaRESUMO
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.