PubMed · 11628313
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R Beauperthuy de Benedetti. 1980. [Not Available].. https://pubmed.ncbi.nlm.nih.gov/11628313/
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Introduction. Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease caused by the loss of the SMN1 gene, with a variable clinical spectrum determined primarily by the number of copies of the SMN2 gene. The development of new therapies underscores the importance of early molecular diagnosis and genotype-phenotype characterization. Objective. To describe 27 years of experience in the molecular diagnosis of SMA at a pediatric referral hospital in Argentina and to evaluate the correlation between SMN2 copy number and the SMA types.Population and methods. A retrospective descriptive study was conducted on 1060 pediatric patients with clinically suspected SMA who were evaluated between 1997 and 2024. Molecular diagnosis was performed using PCR-RFLP and, since 2012, MLPA to determine SMN1 and SMN2 copy number. Genotype-phenotype correlation was evaluated in 260 patients with complete clinical characterization. Results. The diagnosis was confirmed in 513 patients. A homozygous deletion of the SMN1 gene was detected in 99.6% of unrelated cases. The positivity rate increased over time. A significant correlation was observed between the number of SMN2 copies and the type of SMA, with milder phenotypes associated with a higher number of copies. Conclusion. Molecular diagnosis of SMA enabled accurate and timely characterization of patients, avoiding invasive procedures and optimizing therapeutic decision-making. Genotype-phenotype correlation is a fundamental tool for prognosis and clinical management, highlighting the importance of an interdisciplinary approach.
Zoning is a key prescriptive tool for administration and management of protected areas. However, the lack of zoning is common for most protected areas in developing countries and, as a consequence, many protected areas are not effective in achieving the goals for which they were created. In this work, we introduce a quantitative method to expeditiously zone protected areas and we evaluate its ecological implications on hypothetical zoning cases. A real-world application is reported for the Talampaya National Park, a UNESCO World Heritage Site located in Argentina. Our method is a modification of the zoning forest model developed by Bos [Bos, J., 1993. Zoning in forest management: a quadratic assignment problem solved by simulated annealing. Journal of Environmental Management 37, 127-145.]. Main innovations involve a quadratic function of distance between land units, non-reciprocal weights for adjacent land uses (mathematically represented by a non-symmetric matrix), and the possibility of imposing a connectivity constraint. Due to its intrinsic spatial dimension, the zoning problem belongs to the NP-hard class, i.e. a solution can only be obtained in non-polynomial time [Nemhausser, G., Wolsey, L., 1988. Integer and Combinatorial Optimization. John Wiley, New York.]. For that purpose, we applied a simulated annealing heuristic implemented as a FORTRAN language routine. Our innovations were effective in achieving zoning designs more compatible with biological diversity protection. The quadratic distance term facilitated the delineation of core zones for elements of significance; the connectivity constraint minimized fragmentation; non-reciprocal land use weightings contributed to better representing management decisions, and influenced mainly the edge and shape of zones. This quantitative method can assist the zoning process within protected areas by offering many zonation scheme alternatives with minimum cost, time and effort. This ability provides a new tool to improve zoning within protected areas in developing countries.
Two spectral bands of the visible spectrum [0.45-0.52 microm (Blue), 0.52-0.60 microm (Green)] of satellite images obtained by LANDSAT 7 ETM+ have been used in this study to follow the contaminated waters of Medrano Creek when it flows into Río de la Plata River. The former is one of the five fresh watercourses going through the Metropolitan Area of Buenos Aires, Argentina, where 13 million people live. Previous studies have shown that the water quality of Rio de la Plata at the outlet of Medrano Creek has decreased more than 50% as a source of water for human consumption. The non-treated effluents of the textile industry probably affect the water quality. We have developed a model that predicts the water quality index (WQI) of surface waters in the study area and uses linear regression analysis. The model has been validated using a data set of 12 physicochemical parameters obtained during the last 3 years. The potentiality of using satellite images was confirmed by the results: (a) to trace the organic contamination (associated with dyes) in freshwater systems and (b) as tools for decision making in the management of water resources.