GUILHERME LOPES YAMAMOTO
Projetos de Pesquisa
Unidades Organizacionais
Instituto da Criança, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina
LIM/36 - Laboratório de Pediatria Clínica, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
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- Gene expression profile suggesting immunological dysregulation in two Brazilian Bloom's syndrome cases(2020) MONTENEGRO, Marilia M.; QUAIO, Caio R.; PALMEIRA, Patricia; GASPARINI, Yanca; RANGEL-SANTOS, Andreia; DAMASCENO, Julian; NOVAK, Estela M.; GIMENEZ, Thamires M.; YAMAMOTO, Guilherme L.; RONJO, Rachel S.; NOVO-FILHO, Gil M.; CHEHIMI, Samar N.; ZANARDO, Evelin A.; DIAS, Alexandre T.; NASCIMENTO, Amom M.; COSTA, Thais V. M. M.; DUARTE, Alberto J. da S.; COUTINHO, Luiz L.; KIM, Chong A.; KULIKOWSKI, Leslie D.Background Bloom syndrome (BS) is a rare autosomal recessive chromosome instability disorder. The main clinical manifestations are growth deficiency, telangiectasic facial erythema, immunodeficiency, and increased risk to develop neoplasias at early age. Cytogenetic test for sister chromatid exchanges (SCEs) is used as a diagnostic marker for BS. In addition, most patients also present mutations in the & x202f;BLM & x202f;gene, related to defects in the DNA repair mechanism. However, the molecular mechanism behind the pathogenicity of BS is & x202f;still & x202f;not completely understood. Methods We describe two patients confirmed with BS by SCE and molecular analysis. Also, we performed the gene expression profile by the RNA-seq methodology in mRNA transcripts for differential gene expression analysis using as a biological condition for comparison BS versus health controls. Results We detected 216 differentially expressed genes related to immunological pathways such as positive regulation and activation of B cells, immune effector process and absence of difference of DNA repair genes expression. In addition; we also observed differentially expressed genes associated with apoptosis control, such as BCL2L1, CASP7, CDKN1A, E2F2, ITPR, CD274, TNFAIP6, TNFRSF25, TNFRSF13C, and TNFRSF17. Conclusion Our results suggest that the combination of altered expression of genes involved in signaling pathways of immune response and apoptosis control may contribute directly to the main characteristics observed in BS, such as recurrent infections, growth failure, and high risk of cancer. Transcriptome studies of other instability syndromes could allow a more accurate analysis of the relevant gene interactions associated with the destabilization of the genome. This is a first description of the profile of differential gene expression related to immunological aspects detected in patients with BS by RNA-seq.
conferenceObject Severe Osteogenesis imperfecta with oligodontia: think of MESD(2020) MOOSA, S.; YAMAMOTO, G. L.; GARBES, L.; KEUPP, K.; BELEZA-MEIRELES, A.; MORENO, C. A.; VALADARES, E. R.; SOUSA, S. B. de; MAIA, S.; SARAIVA, J.; HONJO, R. S.; KIM, C. A.; MENEZES, H. Cabral de; LAUSCH, E.; LORINI, P. V.; LAMOUNIER JR., A.; CARNIERO, T. C. B.; GIUNTA, C.; ROHRBACH, M.; JANNER, M.; SEMLER, O.; BELEGGIA, F.; LI, Y.; YIGIT, G.; REINTJES, N.; ALTMULLER, J.; NURNBERG, P.; CAVALCANTI, D. P.; ZABEL, B.; WARMAN, M. L.; BERTOLA, D. R.; WOLLNIK, B.; NETZER, C.- Evidence-based Risk Stratification for Sport Medicine Procedures During the COVID-19 Pandemic(2020) HINCKEL, Betina B.; BAUMANN, Charles A.; EJNISMAN, Leandro; CAVINATTO, Leonardo M.; MARTUSIEWICZ, Alexander; TANAKA, Miho J.; TOMPKINS, Marc; SHERMAN, Seth L.; CHAHLA, Jorge A.; FRANK, Rachel; YAMAMOTO, Guilherme L.; BICOS, James; ARENDT, Liza; FITHIAN, Donald; FARR, JackOrthopaedic practices have been markedly affected by the emergence of the COVID-19 pandemic. Despite the ban on elective procedures, it is impossible to define the medical urgency of a case solely on whether a case is on an elective surgery schedule. Orthopaedic surgical procedures should consider COVID-19-associated risks and an assimilation of all available disease dependent, disease independent, and logistical information that is tailored to each patient, institution, and region. Using an evidence-based risk stratification of clinical urgency, we provide a framework for prioritization of orthopaedic sportmedicine procedures that encompasses such factors. This can be used to facilitate the risk-benefit assessment of the timing and setting of a procedure during the COVID-19 pandemic.
- Manifesting carriers of X-linked myotubular myopathy Genetic modifiers modulating the phenotype(2020) SOUZA, Lucas Santos; ALMEIDA, Camila Freitas; YAMAMOTO, Guilherme Lopes; PAVANELLO, Rita de Cassia Mingroni; GURGEL-GIANNETTI, Juliana; COSTA, Silvia Souza da; ANEQUINI, Isabela Pessa; CARMO, Silvana Amanda do; WANG, Jaqueline Yu Ting; SCLIAR, Marilia de Oliveira; CASTELLI, Erick C.; OTTO, Paulo Alberto; ZANOTELI, Edmar; VAINZOF, MarizObjective To analyze the modulation of the phenotype in manifesting carriers of recessive X-linked myotubular myopathy (XLMTM), searching for possible genetic modifiers. Methods Twelve Brazilian families with XLMTM were molecularly and clinically evaluated. In 2 families, 4 of 6 and 2 of 5 manifesting female carriers were identified. These females were studied for X chromosome inactivation. In addition, whole-exome sequencing was performed, looking for possible modifier variants. We also determined the penetrance rate among carriers of the mutations responsible for the condition. Results Mutations in the MTM1 gene were identified in all index patients from the 12 families, being 4 of them novel. In the heterozygotes, X chromosome inactivation was random in 3 of 4 informative manifesting carriers. The disease penetrance rate was estimated to be 30%, compatible with incomplete penetrance. Exome comparative analyses identified variants within a segment of 4.2 Mb on chromosome 19, containing the killer cell immunoglobulin-like receptor cluster of genes that were present in all nonmanifesting carriers and absent in all manifesting carriers. We hypothesized that these killer cell immunoglobulin-like receptor variants may modulate the phenotype, acting as a protective factor in the nonmanifesting carriers. Conclusions Affected XLMTM female carriers have been described with a surprisingly high frequency for a recessive X-linked disease, raising the question about the pattern of inheritance or the role of modifier factors acting on the disease phenotype. We demonstrated the possible existence of genetic mechanisms and variants accountable for the clinical manifestation in these women, which can become future targets for therapies.
- Phenotype-genotype analysis of 242 individuals with RASopathies: 18-year experience of a tertiary center in Brazil(2020) BERTOLA, Debora R.; CASTRO, Matheus A. A.; YAMAMOTO, Guilherme L.; HONJO, Rachel S.; CERONI, Jose Ricardo; BUSCARILLI, Michele M.; FREITAS, Amanda B.; MALAQUIAS, Alexsandra C.; PEREIRA, Alexandre C.; JORGE, Alexander A. L.; PASSOS-BUENO, Maria Rita; KIM, Chong A.We report the clinical and molecular data of a large cohort comprising 242 individuals with RASopathies, from a single Tertiary Center in Brazil, the largest study from Latin America. Noonan syndrome represented 76% of the subjects, with heterozygous variants in nine different genes, mainly PTPN11, SOS1, RAF1, LZTR1, and RIT1, detected by Sanger and next-generation sequencing. The latter was applied to 126 individuals, with a positive yield of 63% in genes of the RAS/MAPK cascade. We present evidence that there are some allelic differences in PTPN11 across distinct populations. We highlight the clinical aspects that pose more medical concerns, such as the cardiac anomalies, bleeding diathesis and proliferative lesions. The genotype-phenotype analysis between the RASopathies showed statistically significant differences in some cardinal features, such as craniofacial and cardiac anomalies, the latter also statistically significant for different genes in Noonan syndrome. We present two individuals with a Noonan syndrome phenotype, one with an atypical, structural cardiac defect, harboring variants in genes mainly associated with isolated hypertrophic cardiomyopathy and discuss the role of these variants in their phenotype.