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1.
Conserv Biol ; 35(5): 1367-1379, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34355419

RESUMO

Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species that trigger either the vulnerability and or the irreplaceability criterion and thus identify a site as a KBA). However, to our knowledge, many of these KBAs have not been validated. Therefore, classical surveys of the taxa used to identify freshwater KBAs (fishes, molluscs, odonates, and aquatic plants) were conducted in Douro (Iberian Peninsula) and Sebou (Morocco) River basins in the Mediterranean Biodiversity Hotspot. Environmental DNA analyses were undertaken in the Moroccan KBAs. There was a mismatch between the supposed and actual presence of trigger species. None of the trigger species were found in 43% and 50% of all KBAs surveyed in the Douro and Sebou basins, respectively. Shortcomings of freshwater KBA identification relate to flawed or lack of distribution data for trigger species. This situation results from a misleading initial identification of KBAs based on poor (or even inaccurate) ecological information or due to increased human disturbance between initial KBA identification and the present. To improve identification of future freshwater KBAs, we suggest selecting trigger species with a more conservative approach; use of local expert knowledge and digital data (to assess habitat quality, species distribution, and potential threats); consideration of the subcatchment when delineating KBAs boundaries; thoughtful consideration of terrestrial special areas for conservation limits; and periodic field validation.


Alarming decline of freshwater trigger species in western Mediterranean Key Biodiversity Areas Resumen La identificación de las áreas clave de biodiversidad (ACB) fue iniciada por la Unión Internacional para la Conservación de la Naturaleza en 2004 con el objetivo de sobreponerse a los sesgos taxonómicos en la selección de áreas importantes para la conservación, incluyendo los ecosistemas de agua dulce. Desde entonces, varias ACB han sido identificadas principalmente con base en la presencia de especies desencadenantes (es decir, especies que desencadenan el criterio de vulnerabilidad o de carácter irremplazable y por lo tanto identifican a un sitio como una ACB). Sin embargo, a nuestro conocimiento, muchas de estas ACB no han sido validadas. Por lo tanto, los censos clásicos de taxones utilizados para identificar las ACB de agua dulce (peces, moluscos, odonatos y plantas acuáticas) fueron realizados en las cuencas de los ríos Duero (Península Ibérica) y Sebou (Marruecos) en el Punto Caliente de Biodiversidad del Mediterráneo. Realizamos análisis de ADN ambiental en las ACB de Marruecos. Hubo una discrepancia entre la supuesta presencia y la actual presencia de especies desencadenantes. Ninguna de las especies desencadenantes se encontró en 43% y 50% de las ACB censadas en las cuencas del Duero y del Sebou, respectivamente. Las deficiencias en la identificación de las ACB de agua dulce están relacionadas con la carencia de datos o datos erróneos sobre la distribución de las especies desencadenantes. Esta situación resulta en una identificación inicial engañosa de las ACB con base en información ecológica deficiente (o incluso incorrecta) o también puede deberse al incremento en las perturbaciones humanas ocurridas entre la identificación de la ACB y el presente. Para mejorar la identificación de ACB de agua dulce en el futuro, sugerimos que la selección de especies desencadenantes se realice con un enfoque más conservador; que se usen el conocimiento local de los expertos y los datos digitales (para evaluar la calidad del hábitat, la distribución de las especies y las amenazas potenciales); que se consideren las subcuencas cuando se delimiten las fronteras de las ACB; que se consideren cuidadosamente las áreas de especies terrestres para los límites de conservación; y que se realicen validaciones periódicas de campo.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Peixes , Água Doce , Humanos
2.
Eur J Paediatr Neurol ; 43: 52-61, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36905830

RESUMO

Neurofibromatosis type 1 (NF1) is a phenotypically heterogenous multisystem cancer predisposition syndrome manifesting in childhood and adolescents. Central nervous system (CNS) manifestations include structural, neurodevelopmental, and neoplastic disease. We aimed to (1) characterize the spectrum of CNS manifestations of NF1 in a paediatric population, (2) explore radiological features in the CNS by image analyses, and (3) correlate genotype with phenotypic expression for those with a genetic diagnosis. We performed a database search in the hospital information system covering the period between January 2017 and December 2020. We evaluated the phenotype by retrospective chart review and imaging analysis. 59 patients were diagnosed with NF1 [median age 10.6 years (range, 1.1-22.6); 31 female] at last follow-up, pathogenic NF1 variants were identified in 26/29. 49/59 patients presented with neurological manifestations including 28 with structural and neurodevelopmental findings, 16 with neurodevelopmental, and 5 with structural findings only. Focal areas of signal intensity (FASI) were identified in 29/39, cerebrovascular anomalies in 4/39. Neurodevelopmental delay was reported in 27/59 patients, learning difficulties in 19/59. Optic pathway gliomas (OPG) were diagnosed in 18/59 patients, 13/59 had low-grade gliomas outside the visual pathways. 12 patients received chemotherapy. Beside the established NF1 microdeletion, neither genotype nor FASI were associated with the neurological phenotype. NF1 was associated with a spectrum of CNS manifestations in at least 83.0% of patients. Regular neuropsychological assessment complementing frequent clinical and ophthalmologic testing for OPG is necessary in the care of each child with NF1.


Assuntos
Neurofibromatose 1 , Glioma do Nervo Óptico , Humanos , Feminino , Neurofibromatose 1/complicações , Neurofibromatose 1/genética , Estudos Retrospectivos , Glioma do Nervo Óptico/diagnóstico , Glioma do Nervo Óptico/epidemiologia , Glioma do Nervo Óptico/genética , Fenótipo , Genótipo
3.
Anticancer Res ; 36(8): 4095-121, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27466519

RESUMO

UNLABELLED: Optic pathway glioma (OPG) is a rare neoplasm and a defining feature of neurofibromatosis type 1 (NF1), a tumor suppressor genetic disorder. OPG predominantly arises during childhood. In contrast to sporadic OPG, this neoplasm frequently appears to show a more favorable course. Outcome appears to depend on localization of tumor; however, the correlation of imaging findings and visual acuity is in general low. Treatment for symptomatic OPG is not well standardized. Furthermore, determination of visual acuity as the most important parameter of follow-up control is often difficult to determine, particularly in children. Focal abnormal signal intensity (FASI) is a characteristic finding on magnetic resonance imaging (MRI) of NF1 patients. The aim of this study was to evaluate clinical and imaging findings of NF1 patients affected with OPG. PATIENTS AND METHODS: Data of 925 NF1 patients with appropriate MRI cranial sectional images (N=1,948) were evaluated. A further 50 patients with cranial computed tomograms were included in the study. We compared imaging and clinical findings with respect to localization of OPG. Furthermore, we compared follow-up in treated individuals to those who were only regularly re-examined. The presence of FASI on MRI was determined and correlated to the occurrence of OPG. Dodge classification was applied to categorize OPG location. RESULTS: OPG was diagnosed in 134 patients. The mean age of patients with symptomatic OPG was 7.6 years (n=57, 42.5%) and 11.6 years (n=77, 57.5%) in asymptomatic patients. The female to male ratio was about 1.1:1. In 48 symptomatic patients, the findings of initial ophthalmological investigations were available. In symptomatic patients, reduced visual acuity was the predominant finding. Strabismus (25%), exophthalmos (22.9%) and amblyopia (20.8%) were most frequently noticed, followed by endrocrinological abnormalities (14.6%). However, these findings did not differ between patients who were treated or who were subjected to a 'wait-and-see' policy. We could not verify an effect of therapy on vision in patients treated for OPG compared to symptomatic patients without treatment. OPG affecting the total optic pathway was more frequently diagnosed in symptomatic patients. FASI did not correlate with functional OPG status. CONCLUSION: OPG in NF1 is symptomatic in slightly less than 50% of affected individuals. This neurological finding may show a wide range of symptoms. At present, no established treatment protocol emerges from the history of the patients of this study and also from the literature. Although the onset of symptomatic OPG is strongly associated with early childhood, late onset of symptomatic OPG is a feature of adult NF1. Research for association of FASI to neurological findings in these patients should be based on other issues than association with OPG.


Assuntos
Neurofibromatose 1/diagnóstico , Glioma do Nervo Óptico/diagnóstico , Adolescente , Adulto , Distribuição por Idade , Criança , Tomada de Decisão Clínica , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Neurofibromatose 1/epidemiologia , Neurofibromatose 1/terapia , Glioma do Nervo Óptico/epidemiologia , Glioma do Nervo Óptico/terapia , Estudos Retrospectivos , Adulto Jovem
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