NIVALDO ALONSO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cirurgia, Faculdade de Medicina - Docente
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/04 - Laboratório de Microcirurgia, Hospital das Clínicas, Faculdade de Medicina - Líder
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/04 - Laboratório de Microcirurgia, Hospital das Clínicas, Faculdade de Medicina - Líder
5 resultados
Resultados de Busca
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- Versatility of the buccinator myomucosal flap in atypical palate reconstructions(2014) FRANCO, Diogo; ROCHA, Diogenes; ARNAUT JR., Marcio; FREITAS, Renato; ALONSO, NivaldoInitially described for the treatment of cleft palate, the anatomical bases of the buccinator myomucosal flap were described by Bozola et al. (1989). A meticulous search found several reports of its use for the correction of post-palatoplasty oronasal fistulas, with only a few reports of its use for other palate-related pathologies. A retrospective analysis was undertaken of patients treated by the Plastic Surgery Units at the Rio de Janeiro Federal University Hospital (HU-UFRJ) and the Sao Paulo University Hospital (HC-USP), suffering from palatal lesions not associated with a cleft palate and treated through the use of buccinator myomucosal flaps. The average age was 47 years, with 70% of the patients being male. Assorted aetiologies were noted for palatal defects. When there was significant damage to the soft palate, a superior base pharyngeal flap was used. Of this total, in 71% of the cases only the buccinator myomucosal flap was used. In all cases, the flaps were unilateral, adequately covering the defects in question. The buccinator myomucosal flap is a good option for reconstructing medium to large palate defects, as it is a flap with good vascularization and dimension, in addition to an ample arc of rotation, with primary closure of the donor site, without adding significant morbidity.
- IRF6 is a Risk Factor for Nonsyndromic Cleft Lip in the Brazilian Population(2012) BRITO, Luciano A.; BASSI, Camila F. S.; MASOTTI, Cibele; MALCHER, Carolina; ROCHA, Katia M.; SCHLESINGER, David; BUENO, Daniela F.; CRUZ, Lucas A.; BARBARA, Ligia K.; BERTOLA, Debora R.; MEYER, Diogo; FRANCO, Diogo; ALONSO, Nivaldo; PASSOS-BUENO, Maria RitaNonsyndromic cleft lip with or without cleft palate (NSCL/P) is a complex disorder with a worldwide incidence estimated at 1:700. Among the putative susceptibility loci, the IRF6 gene and a region at 8q24.21 have been corroborated in different populations. To test the role of IRF6 in NSCL/P predisposition in the Brazilian population, we conducted a structured association study with the SNPs rs642961 and rs590223, respectively, located at 5' and 3' of the IRF6 gene and not in strong linkage disequilibrium (LD), in patients from five different Brazilian locations. We also evaluated the effect of these SNPs in IRF6 expression in mesenchymal stem cells (MSC). We observed association between rs642961 and cleft lip only (CLO) (P = 0.009; odds ratio (OR) for AA genotype = 1.83 [95% Confidence interval (CI), 0.64-5.31]; OR for AG genotype = 1.72 [95% CI, 1.03-2.84]). This association seems to be driven by the affected patients from Barbalha, a location which presents the highest heritability estimate (H-2 = 0.85), and the A allele at rs642961 is acting through a dominant model. No association was detected for the SNP rs590223. We did not find any correlation between expression levels and genotypes of the two loci, and it is possible that these SNPs have a functional role in some specific period of embryogenesis. (C) 2012 Wiley Periodicals, Inc.
- Macrostomia A Spectrum of Deformity(2014) BUONOCORE, Samuel; BROER, P. Niclas; WALKER, Marc E.; FREITAS, Renato da Silva; FRANCO, Diogo; ALONSO, NivaldoBackground Macrostomia is a rare facial cleft, with an incompletely described pathogenesis. This series highlights cases of isolated macrostomia presenting with several distinct phenotypes. We examine phenotypic differences in macrostomia patients, to further elucidate the etiopathogenesis. Materials and Methods We performed a retrospective review of macrostomia patients evaluated during a 10-year period. Patient demographics and clinical features are reported. Results We identified 25 macrostomia patients (13M/12F). Right-sided macrostomia occurred in 15, left-sided macrostomia occurred in 6, and bilateral macrostomia occurred in 4 patients. Of the bilateral cases, 100% existed in isolation of craniofacial microsomia (CFM) or other craniofacial abnormalities. Twelve patients presented with macrostomia in isolation of CFM; in this subgroup, the male-to-female ratio was 1:1. Bilateral macrostomia was present in 33% of patients. Unilateral macrostomia occurred more often on the right (5:2). Phenotypes included simple unilateral or bilateral macrostomia (67%), macrostomia associated with severe diastasis of the cheek musculature (8%), macrostomia associated with lateral facial clefts (17%), and diastasis of cheek musculature without significant macrostomia (8%). Conclusions Macrostomia seen in isolation of CFM presents in phenotypically distinct forms. It is unlikely that a single mechanism is responsible for this range of phenotypes. We believe that both intrauterine trauma and failure of fusion of the mandibular and maxillary processes secondary to an aberration in FGF8 function are responsible. Additionally, diastasis of facial musculature may result from delayed fusion and subsequent decreased mesodermal penetration of the mandibular and maxillary processes.
- Genetic Contribution for Non-Syndromic Cleft Lip With or Without Cleft Palate (NS CL/P) in Different Regions of Brazil and Implications for Association Studies(2011) BRITO, Luciano A.; CRUZ, Lucas A.; ROCHA, Katia M.; BARBARA, Ligia K.; SILVA, Camila B. F.; BUENO, Daniela F.; AGUENA, Meire; BERTOLA, Debora R.; FRANCO, Diogo; COSTA, Andre M.; ALONSO, Nivaldo; OTTO, Paulo A.; PASSOS-BUENO, Maria RitaNon-syndromic cleft lip with or without cleft palate (NS CL/P) is a complex disease in which heritability estimates vary widely depending on the population studied. To evaluate the importance of genetic contribution to NS CL/P in the Brazilian population, we conducted a study with 1,042 families from five different locations (Santarem, Fortaleza, Barbalha, Maceio, and Rio de Janeiro). We also evaluated the role of consanguinity and ethnic background. The proportion of familial cases varied significantly across locations, with the highest values found in Santarem (44%) and the lowest in Maceio (23%). Heritability estimates showed a higher genetic contribution to NS CL/P in Barbalha (85%), followed by Santarem (71%), Rio de Janeiro (70%), Fortaleza (64%), and Maceio (45%). Ancestry was not correlated with the occurrence of NS CL/P or with the variability in heritability. Only in Rio de Janeiro was the coefficient of inbreeding significantly larger in NS CL/P families than in the local population. Recurrence risk for the total sample was approximately 1.5-1.6%, varying according to the location studied (0.6-0.7% in Maceio to 2.2-2.8% in Barbalha). Our findings show that the degree of genetic contribution to NS CL/P varies according to the geographic region studied, and this difference cannot be attributed to consanguinity or ancestry. These findings suggest that Barbalha is a promising region for genetic studies. The data presented here will be useful in interpreting results from molecular analyses and show that care must be taken when pooling samples from different populations for association studies. (C) 2011 Wiley-Liss, Inc.
- Region 8q24 Is a Susceptibility Locus for Nonsyndromic Oral Clefting in Brazil(2012) BRITO, Luciano Abreu; PARANAIBA, Livia Maris Ribeiro; BASSI, Camila Fernandes Silva; MASOTTI, Cibele; MALCHER, Carolina; SCHLESINGER, David; ROCHA, Katia Maria; CRUZ, Lucas Alvizi; BARBARA, Ligia Kobayashi; ALONSO, Nivaldo; FRANCO, Diogo; BAGORDAKIS, Elizabete; MARTELLI JR., Hercilio; MEYER, Diogo; COLETTA, Ricardo D.; PASSOS-BUENO, Maria RitaBACKGROUND: Nonsyndromic cleft lip with or without cleft palate is a relatively common craniofacial defect with multifactorial inheritance. The association of the rs987525 single nucleotide variant, located in a gene desert at 8q24.21 region, has been consistently replicated in European populations. We performed a structured association approach combined with transcriptional analysis of the MYC gene to dissect the role of rs987525 in oral clefting susceptibility in the ethnically admixed Brazilian population. METHODS: We performed the association study conditioned on the individual ancestry proportions in a sample of 563 patients and 336 controls, and in an independent sample of 221 patients and 261 controls. The correlation between rs987525 genotypes and MYC transcriptional levels in orbicularis oris muscle mesenchymal stem cells was also investigated in 42 patients and 4 controls. RESULTS: We found a significant association in the larger sample (p = 0.0016; OR = 1.80 [95% confidence interval {CI}, 1.21-2.69], for heterozygous genotype, and 2.71 [95% CI, 1.47-4.96] for homozygous genotype). We did not find a significant correlation between rs987525 genotypes and MYC transcriptional levels (p = 0.14; r = -0.22, Spearman Correlation). CONCLUSIONS: We present a positive association of rs987525 in the Brazilian population for the first time, and it is likely that the European contribution to our population is driving this association. We also cannot discard a role of rs987515 in MYC regulation, because this locus behaves as an expression quantitative locus of MYC in another tissue. Birth Defects Research (Part A) 94:464-468, 2012. (C) 2012 Wiley Periodicals, Inc.