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1.
PLoS Genet ; 7(7): e1002173, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21779178

RESUMEN

In this study, we used deletions at 22q13, which represent a substantial source of human pathology (Phelan/McDermid syndrome), as a model for investigating the molecular mechanisms of terminal deletions that are currently poorly understood. We characterized at the molecular level the genomic rearrangement in 44 unrelated patients with 22q13 monosomy resulting from simple terminal deletions (72%), ring chromosomes (14%), and unbalanced translocations (7%). We also discovered interstitial deletions between 17-74 kb in 9% of the patients. Haploinsufficiency of the SHANK3 gene, confirmed in all rearrangements, is very likely the cause of the major neurological features associated with PMS. SHANK3 mutations can also result in language and/or social interaction disabilities. We determined the breakpoint junctions in 29 cases, providing a realistic snapshot of the variety of mechanisms driving non-recurrent deletion and repair at chromosome ends. De novo telomere synthesis and telomere capture are used to repair terminal deletions; non-homologous end-joining or microhomology-mediated break-induced replication is probably involved in ring 22 formation and translocations; non-homologous end-joining and fork stalling and template switching prevail in cases with interstitial 22q13.3. For the first time, we also demonstrated that distinct stabilizing events of the same terminal deletion can occur in different early embryonic cells, proving that terminal deletions can be repaired by multistep healing events and supporting the recent hypothesis that rare pathogenic germline rearrangements may have mitotic origin. Finally, the progressive clinical deterioration observed throughout the longitudinal medical history of three subjects over forty years supports the hypothesis of a role for SHANK3 haploinsufficiency in neurological deterioration, in addition to its involvement in the neurobehavioral phenotype of PMS.


Asunto(s)
Deleción Cromosómica , Trastornos de los Cromosomas/genética , Cromosomas Humanos Par 22/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Niño , Preescolar , Hibridación Genómica Comparativa , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Padres , Cromosomas en Anillo , Eliminación de Secuencia/genética , Translocación Genética , Adulto Joven
2.
Am J Hum Genet ; 85(3): 394-400, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19716111

RESUMEN

Submicroscopic copy-number variations make a considerable contribution to the genetic etiology of human disease. We have analyzed subjects with idiopathic mental retardation (MR) by using whole-genome oligonucleotide-based array comparative genomic hybridization (aCGH) and identified familial and de novo recurrent Xp11.22-p11.23 duplications in males and females with MR, speech delay, and a peculiar electroencephalographic (EEG) pattern in childhood. The size of the duplications ranges from 0.8-9.2 Mb. Most affected females show preferential activation of the duplicated X chromosome. Carriers of the smallest duplication show X-linked recessive inheritance. All other affected individuals present dominant expression and comparable clinical phenotypes irrespective of sex, duplication size, and X-inactivation pattern. The majority of the rearrangements are mediated by recombination between flanking complex segmental duplications. The identification of common clinical features, including the typical EEG pattern, predisposing genomic structure, and peculiar X-inactivation pattern, suggests that duplication of Xp11.22-p11.23 constitutes a previously undescribed syndrome.


Asunto(s)
Cromosomas Humanos X/genética , Electroencefalografía , Duplicación de Gen , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/genética , Trastornos del Desarrollo del Lenguaje/complicaciones , Trastornos del Desarrollo del Lenguaje/genética , Femenino , Humanos , Masculino , Linaje
3.
Eur J Hum Genet ; 16(12): 1443-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18648397

RESUMEN

Most patients with an interstitial deletion of 6q16 have Prader-Willi-like phenotype, featuring obesity, hypotonia, short hands and feet, and developmental delay. In all reported studies, the chromosome rearrangement was detected by karyotype analysis, which provides an overview of the entire genome but has limited resolution. Here we describe a detailed clinical presentation of five patients, two of whom were previously reported, with overlapping interstitial 6q16 deletions and Prader-Willi-like phenotype. Our patients share the following main features with previously reported cases: global developmental delay, hypotonia, obesity, hyperphagia, and eye/vision anomalies. All rearrangement breakpoints have been accurately defined through array-CGH at about 100 Kb resolution. We were able to narrow the shortest region of deletion overlap for the presumed gene(s) involved in the Prader-Willi-like syndrome to 4.1 Mb located at 6q16.1q16.2. Our results support the evidence that haploinsufficiency of the SIM1 gene is responsible for obesity in these patients. A possible involvement of the GRIK2 gene in autistic-like behaviour, of POPDC3 in heart development, and of MCHR2 in the control of feeding behaviour and energy metabolism is also hypothesized.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 6 , Fenotipo , Síndrome de Prader-Willi/genética , Adolescente , Adulto , Preescolar , Mapeo Cromosómico , Análisis Citogenético , Femenino , Genotipo , Humanos , Lactante , Masculino
5.
Brain ; 130(Pt 10): 2646-60, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17872929

RESUMEN

Acquired cerebellar lesions in adults and children can lead to the development of a complex behavioural pattern termed 'Cerebellar Cognitive Affective Syndrome' (Schmahmann and Sherman, Brain, 1998; 121: 561-79), which is characterized by reduced cognitive efficiency associated with specific neuropsychological deficits (executive and visuospatial disorders), expressive language disorders (mild agrammatism and anomia) and affective disorders with blunting of affect. It is not known whether a symptomatological picture such as this can also be found in congenital cerebellar malformations. We studied the behavioural developmental profile of 27 patients including children and adults with congenital malformations confined to the cerebellum, the largest studied sample to date. Extensive clinical and neuropsychological investigations highlight the presence of a wide range of disorders supporting the important role played by the cerebellum in the acquisition of higher-order cognitive and affective skills. The type and extent of cerebral reorganization processes in the presence of malformative lesions are difficult to predict and may possibly account for the variability of clinical phenotypes. It is, therefore, more difficult to identify a syndromic picture defined as exactly as is the case with acquired lesions. However, the pattern of deficits that we document is in remarkable agreement with the general profile of the Cerebellar Cognitive Affective Syndrome. Malformations affecting the cerebellar vermis induce affective and social disorders and evolve towards more unfavourable pictures often associated with an autistic symptomatology. Malformations of cerebellar hemispheres are more frequently associated with selective neuropsychological deficits involving mainly executive functions and visuospatial and linguistic abilities. Motor deficits are generally less severe, and tend to improve slowly and progressively, in some cases reaching almost complete functionality. Finally, the overall favourable evolution with an onset of skills in advanced age in a consistent subset of subjects suggests that individual follow-ups should be performed in order to monitor the quality and stability of impairments and acquired abilities over time.


Asunto(s)
Cerebelo/anomalías , Trastornos del Conocimiento/etiología , Discapacidades del Desarrollo/etiología , Trastornos del Humor/etiología , Adolescente , Trastorno Autístico/etiología , Trastorno Autístico/patología , Cerebelo/patología , Niño , Preescolar , Trastornos del Conocimiento/patología , Discapacidades del Desarrollo/patología , Femenino , Estudios de Seguimiento , Humanos , Trastornos del Desarrollo del Lenguaje/etiología , Trastornos del Desarrollo del Lenguaje/patología , Imagen por Resonancia Magnética , Masculino , Trastornos del Humor/patología , Pruebas Neuropsicológicas , Desempeño Psicomotor
6.
Eur J Med Genet ; 50(1): 54-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17055792

RESUMEN

The diagnosis of a subtelomeric rearrangement has immediate impact on counseling, particularly in the case of familial rearrangements. However, the existence of subtelomeric imbalances with absent phenotypic effects may hamper genetic counseling, particularly when the rearrangement has not been previously described. We report on a new subtelomeric polymorphism, consisting of a familial subtelomeric rearrangement of chromosome 19 resulting in distal trisomy for 21q, detected in a child with Angelman Syndrome (AS) due to an UBE3A mutation. This report shows that new, previously unknown, benign subtelomeric variants may complicate the correct clinical diagnosis.


Asunto(s)
Síndrome de Down/genética , Variación Genética , Telómero/genética , Síndrome de Angelman/genética , Preescolar , Cromosomas Humanos Par 19/genética , Femenino , Humanos , Translocación Genética , Ubiquitina-Proteína Ligasas/genética
7.
Pediatr Neurol ; 34(3): 186-93, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16504787

RESUMEN

This study reports the clinical features of 63 patients with agenesis of the corpus callosum who received in-depth genetic, clinical, and laboratory testing with the aim to contribute to a better description of the large spectrum of associated malformations and to assist clinicians in the diagnosis. Thirty patients manifested complete agenesis and 33 patients displayed partial agenesis. Other associated nervous system malformations were detected in 14 patients with partial agenesis of the corpus callosum (mostly correlated to posterior fossa malformations) and in 10 patients with complete agenesis (more frequently associated with malformations of cortical development). Involvement of organs and apparatus other than the nervous system was present in 41 patients (ascribed to known syndromes in 21 cases). Cytogenetically detectable chromosomal abnormalities (7 patients) and subtelomeric rearrangements (3 patients) were found. Neuromotor skills were impaired in almost all cases (58/63). Mental retardation of different severity was present in 52 cases, whereas 2 patients were borderline and 9 patients had normal intelligence quotient. This study demonstrates that there is no unique prognosis for agenesis of the corpus callosum as this condition is associated with a broad range of clinical manifestations, oscillating between the limits of the norm and severe psychomotor delay.


Asunto(s)
Anomalías Múltiples/genética , Agenesia del Cuerpo Calloso , Malformaciones del Sistema Nervioso/genética , Anomalías Múltiples/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Reordenamiento Génico/genética , Humanos , Lactante , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Masculino , Malformaciones del Sistema Nervioso/diagnóstico , Síndrome
8.
Am J Med Genet ; 112(2): 154-9, 2002 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-12244548

RESUMEN

We studied the case of a girl with a partial 9p duplication, dup(9)(p22.1 --> p13.1). Molecular cytogenetics studies defined the chromosome 9 rearrangement as a direct duplication of 20 Mb from D9S1213 to D9S52. Microsatellite analysis demonstrated the presence of a double dosage of the paternal alleles and demonstrated that the duplication occurred between sister chromatids. The patient's phenotype was almost normal, with a few minor anomalies (dolichocephaly, crowded teeth, high arched palate) and normal IQ. The breakpoint's location in this patient and previously reported cases suggest that the critical region for the 9p duplication syndrome lies within a 6-Mb portion of chromosome 9p22 between markers D9S267 and D9S1213.


Asunto(s)
Cromosomas Humanos Par 9 , Anomalías Congénitas/genética , Duplicación de Gen , Niño , Mapeo Cromosómico , Citogenética , Femenino , Humanos , Hibridación Fluorescente in Situ , Inteligencia/genética , Reacción en Cadena de la Polimerasa
9.
J Child Neurol ; 18(1): 21-5, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12661934

RESUMEN

It has recently been demonstrated that patients with Angelman's syndrome who exhibited a deletion on cytogenetic tests show more severe clinical pictures with drug-resistant epilepsy than patients with Angelman's syndrome not carrying the deletion. To verify if this difference in clinical severity can be attributed to genes for the three gamma-aminobutyric acid (GABA)A receptor subunits (GABRB3, GABRA5, GABRG3) located in the deleted region, a possible modification of peripheral markers of the GABAergic system was investigated in 12 subjects with Angelman's syndrome and 20 age-matched subjects (8 with idiopathic epilepsy and 12 not affected by neurologic diseases). The results confirmed a more severe clinical picture, and epilepsy syndrome in particular, in Angelman's syndrome patients with deletions versus patients without deletions. In contrast, biochemical study (based on dosage of plasma levels of GABA and diazepam binding inhibitor, an endogenous ligand of GABAA and peripheral benzodiazepine receptors, showed contradictory results: patients with Angelman's syndrome showed significantly higher levels of GABA and diazepam binding inhibitor than patients without neurologic impairment but significantly lower levels than epileptic controls.


Asunto(s)
Síndrome de Angelman/diagnóstico , Inhibidor de la Unión a Diazepam/sangre , Epilepsias Parciales/diagnóstico , Epilepsia Generalizada/diagnóstico , Receptores de GABA-A/sangre , Ácido gamma-Aminobutírico/sangre , Adolescente , Adulto , Síndrome de Angelman/sangre , Síndrome de Angelman/genética , Niño , Preescolar , Bandeo Cromosómico , Deleción Cromosómica , Epilepsias Parciales/sangre , Epilepsias Parciales/genética , Epilepsia Generalizada/sangre , Epilepsia Generalizada/genética , Femenino , Estudios de Seguimiento , Humanos , Masculino , Fenotipo , Valor Predictivo de las Pruebas , Receptores de GABA-A/genética
10.
Res Dev Disabil ; 34(9): 2543-50, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23751299

RESUMEN

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common diagnosis for children and adolescents, although the reported estimates for prevalence are extremely variable worldwide. In the present work we investigate the prevalence of ADHD in a sample of Italian students in a study divided in two phases. In Phase I, a total of 6183 schoolchildren (3178 males and 3005 females, aged range 5-15 years) were screened using the SDAI rating scale for teachers. In Phase II, the parents of children and adolescents who met high screen criteria according to SDAI (cut-off>14; n=471, 7.3%) were invited to complete a specific clinical-diagnostic assessment for ADHD with the help of an experienced clinician. Within the entire sample, 107 children dropped out and 12 had mental retardation, whereas 332 subjects (278 males and 54 females, age range 5-14 years) completed the Phase II of the study. One hundred ninety subjects (163 males and 27 females, male: female ratio 6:1, mean age 8 years) were diagnosed with ADHD, indicating a prevalence of 3%. ADHD subtypes included the following: combined (n=108; 56.8%), inattentive (n=48; 25.2%) and hyperactive/impulsive (n=33; 17.3%). Our findings are in line with other reports of ADHD prevalence in the European Countries, and may contribute to underline the impact of this phenomenon in the population, and the need of achieving an improvement in the quality of the public health mental service for the prevention and treatment of ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Tamizaje Masivo , Estudiantes/estadística & datos numéricos , Adolescente , Niño , Preescolar , Docentes , Femenino , Humanos , Italia/epidemiología , Masculino , Padres , Prevalencia , Índice de Severidad de la Enfermedad
11.
Rev. bras. ciênc. mov ; 25(1): 151-167, jan.-mar. 2017. fig, graf, tab
Artículo en Portugués | LILACS | ID: biblio-881040

RESUMEN

Analisar uma política pública em uma gestão governamental implica, necessariamente, uma apreciação da engenharia institucional, bem como dos traços constitutivos dos programas, projetos e ações formulados e implementados. Implica, sobretudo, descobrir o que os governos fazem, porque fazem e que diferença isso faz, porque a política pública pode influenciar a vida de todos, dado que os processos e resultados de políticas sempre envolvem vários grupos sociais. Nesse contexto, esse texto teve como objetivo descrever e analisar o financiamento das Políticas Públicas de Esporte e Lazer do Município de Santarém ­ PA, no período de 2005-2012. Realizamos uma pesquisa qualitativa, por meio de uma combinação de pesquisa bibliográfica, documental e de campo. Os documentos analisados foram: Relatórios e Planejamentos da Assessoria de Esporte e Lazer (AEL), revistas com as mensagens da exprefeita à Câmara Municipal, Leis Orçamentárias Anuais e o Plano Plurianual. O instrumento para a coleta de dados da pesquisa de campo foi a entrevista semiestruturada realizada com doze (12) gestores e os dados foram analisados pela técnica de análise de conteúdo. Constatamos que o financiamento para o desenvolvimento das ações da AEL apresentou uma evolução e foi ampliado, mesmo não sendo considerado ideal, pelos os sujeitos da pesquisa. Identificamos que apesar de estudos demonstrarem maior investimento no esporte de alto rendimento, principalmente na esfera federal, o município analisado investiu um montante significativo de recurso nos esportes de participação e educacional. Por fim, foi possível identificar o montante investido pelo Ministério do Esporte por meio de programas e projetos sociais de esporte e lazer...(AU)


The process of analyzing a public policy from a governmental management perspective thus requires an appreciation of institutional engineering, plus understanding of the distinguishing traits of the formulated and implemented programs, projects and actions, which above all, involves the discovery of what governments actually do, why they perform such actions and the differences these governments actually make, inasmuch that such public policies are able to influence the lives of everyone affected by such issues at both public policy and political level, with the processes and results of such policies involving various social groups. The purpose of this study is to describe and analyze financing of public policies in the municipality of Santarém, in the Brazilian state of Pará between the 2005 and 2012 management period. We conduct qualitative research through a combination of bibliographical, documental and field research studies. The documents analyzed were: Reports and Planning of the Sport and Leisure Office (AEL), magazines with messages from the former mayor of the Municipal Council, Annual Budget Laws, the Multi-annual Plan, and the Government "change will advance" Plan. The instruments used for the collection of data in the field were a series of semi-structured interviews with a total of 12 (twelve) managers. The details were then analyzed using the content analysis technique. With financing being provided for the development of AEL activities, with significant development having taken place and investments having increased, albeit in a less than ideal manner, in accordance with statements of the interviewed subjects. We found that although studies show a greater investment in high performance sport, especially at the federal level, the analyzed municipality has invested a significant amount of resource in sports participation and educational. Finally, it was possible to identify the amount invested by the Ministry of Sports through social programs and projects for sports and leisure...(AU)


Asunto(s)
Humanos , Masculino , Femenino , Financiación del Capital , Actividades Recreativas , Deportes , Sociedades
12.
Eur J Paediatr Neurol ; 16(6): 636-41, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22464827

RESUMEN

BACKGROUND AND OBJECTIVES: Pallister-Killian syndrome (PKS) is a rare genetic disorder caused by a tissue-limited mosaic supernumerary isochromosome 12p. Typical facial dysmorphisms, pigmentary abnormalities, and some major malformations are frequently present. Neurological manifestations include mental retardation, hypotonia, and seizures. Epilepsy incidence ranged from 39 to 59% in a previously reported series. No specific clinical and EEG phenotype has ever been reported to describe seizure features, electroclinical patterns, and response to therapy in PKS. METHODS: This was a multicentre study conducted on 13 Italian children with PKS, as diagnosed by clinical phenotype and confirmed in cultured fibroblasts. All patients underwent several polygraphic video-EEG recordings and brain magnetic resonance imaging. RESULTS AND CONCLUSIONS: All the patients presented with epilepsy and seizures that started at a mean age of 19 months. In six cases, epilepsy started with epileptic spasms (ES) combined with focal seizures in another case. In four cases, seizures were focal, and this was followed by ES in two patients. In only two cases, epilepsy started with myoclonic seizures, and spasms were never observed. The study provides further evidence that epilepsy is a part of the phenotype of PKS, although a specific clinical and EEG pattern could not be identified. Our cases show how ES with late- or first-year onset is the most common type of seizure. Despite a variable prognosis in terms of response to therapy, a significant proportion of patients achieved good seizure control.


Asunto(s)
Trastornos de los Cromosomas/fisiopatología , Electroencefalografía , Convulsiones/etiología , Convulsiones/fisiopatología , Adolescente , Edad de Inicio , Niño , Preescolar , Trastornos de los Cromosomas/genética , Cromosomas Humanos Par 12/genética , Electromiografía , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Humanos , Lactante , Italia , Imagen por Resonancia Magnética , Masculino , Tetrasomía/fisiopatología , Resultado del Tratamiento
13.
Eur J Hum Genet ; 18(10): 1133-40, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20461111

RESUMEN

Cohen syndrome is a rare, clinically variable autosomal recessive disorder characterized by mental retardation, postnatal microcephaly, facial dysmorphisms, ocular abnormalities and intermittent neutropenia. Mutations in the COH1 gene have been found in patients from different ethnic origins. However, a high percentage of patients have only one or no mutated allele. To investigate whether COH1 copy number changes account for missed mutations, we used multiplex ligation-dependent probe amplification (MLPA) to test a group of 14 patients with Cohen syndrome. This analysis has allowed us to identify multi-exonic deletions in 11 alleles and duplications in 4 alleles. Considering our previous study, COH1 copy number variations represent 42% of total mutated alleles. To our knowledge, COH1 intragenic duplications have never been reported in Cohen syndrome. The three duplications encompassed exons 4-13, 20-30 and 57-60, respectively. Interestingly, four deletions showed the same exon coverage (exons 6-16) with respect to a deletion recently reported in a large Greek consanguineous family. Haplotype analysis suggested a possible founder effect in the Mediterranean basin. The use of MLPA was therefore crucial in identifying mutated alleles undetected by traditional techniques and in defining the extent of the deletions/duplications. Given the high percentage of identified copy number variations, we suggest that this technique could be used as the initial screening method for molecular diagnosis of Cohen syndrome.


Asunto(s)
Eliminación de Gen , Duplicación de Gen , Proteínas de Transporte Vesicular/genética , Adolescente , Adulto , Secuencia de Bases , Niño , Preescolar , Variaciones en el Número de Copia de ADN , Análisis Mutacional de ADN , Discapacidades del Desarrollo/genética , Dedos/anomalías , Dosificación de Gen , Genes Recesivos , Haplotipos , Humanos , Lactante , Discapacidad Intelectual/genética , Microcefalia/genética , Persona de Mediana Edad , Técnicas de Sonda Molecular , Hipotonía Muscular/genética , Miopía/genética , Obesidad/genética , Reacción en Cadena de la Polimerasa , Degeneración Retiniana
14.
J Hum Genet ; 52(12): 1011-1017, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17990063

RESUMEN

Cohen syndrome is an autosomal recessive disorder with variability in the clinical manifestations, characterized by developmental delay, visual disability, facial dysmorphisms and intermittent neutropenia. We described a cohort of 10 patients affected by Cohen syndrome from nine Italian families ranging from 5 to 52 years at assessment. Characteristic age related facial changes were well documented. Visual anomalies, namely retinopathy and myopia, were present in 9/10 patients (retinopathy in 9/10 and myopia in 8/10). Truncal obesity has been described in all patients older than 6 years (8/8). DNA samples from all patients were analyzed for mutations in COH1 by DHPLC. We detected 15 COH1 alterations most of them were truncating mutations, only one being a missense change. Partial gene deletions have been found in two families. Most mutations were private. Two were already reported in the literature just once. A single base deletion leading to p.T3708fs3769, never reported before, was found in three apparently unrelated families deriving from a restricted area of the Veneto's lowland, between Padova town and Tagliamento river, in heterozygous state. Given the geographical conformation of this region, which is neither geographically or culturally isolated, a recent origin of the mutation could be hypothesized.


Asunto(s)
Anomalías Múltiples/genética , Discapacidades del Desarrollo/genética , Mutación , Proteínas de Transporte Vesicular/genética , Adolescente , Adulto , Niño , Estudios de Cohortes , Anomalías Craneofaciales/genética , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Neutropenia/genética , Obesidad/genética , Síndrome , Trastornos de la Visión/genética
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