RESUMEN
INTRODUCTION: Late infantile neuronal ceroid lipofuscinosis is an autosomal recessive disease caused by mutations in the CLN2/TPP1 gene, with secondary enzyme deficiency. In classical phenotypes, initial symptoms include seizures and delayed language development between 2 and 4 years of age. This article describes the presentation of CLN2 disease in a cohort of Colombian patients, as well as the impact of treatment on the course and progression of the disease. METHODS: Case series report of 8 patients with a confirmed diagnosis of neuronal ceroid lipofuscinosis treated with cerliponase alfa who remained on clinical and paraclinical follow-up for up to 24 months before and after treatment. RESULTS: An atypical phenotype, associated with initial symptoms and late diagnosis, was present in 5/8 patients. The most frequent symptoms were seizures and developmental delay, with age of onset at 24 months (classical phenotype) and 48 months (atypical phenotype). A novel mutation (c.1438G > A) was found in two siblings. All of the patients received cerliponase alfa, and there were no serious adverse events. No decline in the clinical status greater than 2 points on Hamburg, Weill Cornell and CNL2 clinical assessment scale was observed during follow-up after treatment initiation. CONCLUSION: This is the first case series reported for neuronal ceroid lipofuscinosis patients in Colombia. In contrast with other reports, the majority of cases reported here displayed an atypical phenotype. Our study highlights the importance of early diagnosis and timely initiation of therapy, which is a feasible therapy, well tolerated by patients and accepted by caregivers in this country, generating a positive impact in the quality of life of CLN2 patients and on disease outcome.
RESUMEN
Inflorescences of Tradescantia clone 4430 were exposed to different concentrations of radon (Rn) gas (0.85, 12.10, 36.50 and 98.16 kBq/m3) from plants placed in an acrylic chamber that received radon from a container with pitchblende (containing uranium mineral). The exposure time was 24 h, afterwards the plants were left for 6 h in water and constantly aerated. Positive control plants were irradiated with gamma rays (0.8 Gy) and negative control plants received ambient air only (the background measurement had a mean of 0.38 kBq/m3). Micronuclei (MCN) in the tetrads induced by alpha particles emitted from Rn were tabulated and a linear concentration response was obtained. The potency of radon to induce MCN from the slope of the regression line was 0.13 MCN/kBq/m3 of alpha-radiation. Radon could reach the anthers by diffusion through the aerial spaces within the buds.