VINICIUS NAHIME DE BRITO
Projetos de Pesquisa
Unidades Organizacionais
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
11 resultados
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Agora exibindo 1 - 10 de 11
conferenceObject Copy Number Variants in Patients with Congenital Hypopituitarism Associated with Complex Phenotypes(2015) CORREA, F.; FRANCA, M.; CANTON, A.; OTTO, A.; COSTALONGA, E.; BRITO, V; CARVALHO, L.; COSTA, S.; ARNHOLD, I; JORGE, A.; ROSENBERG, C.; MENDONCA, B.conferenceObject Peripheral Precocious Puberty in Girls with Mccune-Albright Syndrome: Treatment and Outcomes(2015) BARROSO, P.; RAMOS, C.; SILVA, M.; LIMA, L.; BESSA, D.; ARNHOLD, I; MENDONCA, B.; LATRONICO, A.; BRITO, VbookPart Adiposidade e puberdade(2015) BRITO, Vinicius Nahime; LATRONICO, Ana Cláudia- FGFR1 and PROKR2 rare variants found in patients with combined pituitary hormone deficiencies(2015) CORREA, Fernanda A.; TRARBACH, Ericka B.; TUSSET, Cintia; LATRONICO, Ana Claudia; MONTENEGRO, Luciana R.; CARVALHO, Luciani R.; FRANCA, Marcela M.; OTTO, Aline P.; COSTALONGA, Everlayny F.; BRITO, Vinicius N.; ABREU, Ana Paula; NISHI, Mirian Y.; JORGE, Alexander A. L.; ARNHOLD, Ivo J. P.; SIDIS, Yisrael; PITTELOUD, Nelly; MENDONCA, Berenice B.The genetic aetiology of congenital hypopituitarism (CH) is not entirely elucidated. FGFR1 and PROKR2 loss-of-function mutations are classically involved in hypogonadotrophic hypogonadism (HH), however, due to the clinical and genetic overlap of HH and CH; these genes may also be involved in the pathogenesis of CH. Using a candidate gene approach, we screened 156 Brazilian patients with combined pituitary hormone deficiencies (CPHD) for loss-of-function mutations in FGFR1 and PROKR2. We identified three FGFR1 variants (p.Arg448Trp, p.Ser107Leu and p.Pro772Ser) in four unrelated patients (two males) and two PROKR2 variants (p. Arg85Cys and p. Arg248Glu) in two unrelated female patients. Five of the six patients harbouring the variants had a first-degree relative that was an unaffected carrier of it. Results of functional studies indicated that the new FGFR1 variant p.Arg448Trp is a loss-of-function variant, while p.Ser107Leu and p.Pro772Ser present signalling activity similar to the wild-type form. Regarding PROKR2 variants, results from previous functional studies indicated that p.Arg85Cys moderately compromises receptor signalling through both MAPK and Ca2+ pathways while p.Arg248Glu decreases calcium mobilization but has normal MAPK activity. The presence of loss-of-function variants of FGFR1 and PROKR2 in our patients with CPHD is indicative of an adjuvant and/or modifier effect of these rare variants on the phenotype. The presence of the same variants in unaffected relatives implies that they cannot solely cause the phenotype. Other associated genetic and/or environmental modifiers may play a role in the aetiology of this condition.
conferenceObject Long-Term Evaluation of Patients with Testotoxicosis(2015) SILVA, M. Cunha; BRITO, V Nahime; BESSA, D.; RAMOS, C.; LIMA, L.; BARROSO, P.; ARNHOLD, I; MENDONCA, B.; LATRONICO, A.- Quality of life in a large cohort of adult Brazilian patients with 46,XX and 46,XY disorders of sex development from a single tertiary centre(2015) AMARAL, Rita Cassia; INACIO, Marlene; BRITO, Vinicius N.; BACHEGA, Tania A. S. S.; OLIVEIRA JR., Ari A.; DOMENICE, Sorahia; DENES, Francisco T.; SIRCILI, Maria Helena; ARNHOLD, Ivo J. P.; MADUREIRA, Guiomar; GOMES, Larissa; COSTA, Elaine M. F.; MENDONCA, Berenice B.ObjectiveFew studies have focused on the quality of life (QoL) of patients with disorders of sex development (DSD). Our aim was to evaluate QoL in DSD patients with defined diagnoses followed until adulthood in a single tertiary centre. Patients and MethodsAdult patients with DSD (56 patients with 46,XX DSD - 49 with female social sex and 7 with male social sex as well as 88 patients with 46,XY DSD - 54 with female social sex and 34 with male social sex). MeasurementsQoL using WHOQOL-Bref questionnaire. ResultsBoth patients with 46,XX DSD and patients with 46,XY DSD had similar QoL scores on the WHOQOL-Bref, comparable to the scores of the Brazilian general population. The chronological age at the start of treatment was negatively and significantly associated with general QoL score. Patients with male social sex DSD had better scores on the psychological domain than patients with female social sex DSD, as found in the Brazilian general population. In addition, among the 46,XY DSD group, the male social sex patients had better QoL compared with the female social sex patients. There was a positive and significant correlation between sexual performance and general QoL, although it explained only 4% of the variability of the general QoL score. The most influencing variables were general health, positive feelings and spirituality, religion and personal beliefs, each of them contributing with 18% of the variability of the general QoL score. ConclusionOur large cohort of adult patients with DSD, which was followed by a multidisciplinary team in a single tertiary centre, had good QoL in adulthood; in addition, late treatment compromised the QoL of patients with DSD, whereas sexual performance has little influence on QoL.
- Puberty: When is it normal?(2015) BRITO, Vinicius Nahime; LATRONICO, Ana Claudia
- A new pathway in the control of the initiation of puberty: the MKRN3 gene(2015) ABREU, Ana Paula; MACEDO, Delanie B.; BRITO, Vinicius N.; KAISER, Ursula B.; LATRONICO, Ana ClaudiaPubertal timing is influenced by complex interactions among genetic, nutritional, environmental, and socioeconomic factors. The role of MKRN3, an imprinted gene located in the Prader-Willi syndrome critical region (chromosome 15q11-13), in pubertal initiation was first described in 2013 after the identification of deleterious MKRN3 mutations in five families with central precocious puberty (CPP) using whole-exome sequencing analysis. Since then, additional loss-of-function mutations of MKRN3 have been associated with the inherited premature sexual development phenotype in girls and boys from different ethnic groups. In all of these families, segregation analysis clearly demonstrated autosomal dominant inheritance with complete penetrance, but with exclusive paternal transmission, consistent with the monoallelic expression of MKRN3 (a maternally imprinted gene). Interestingly, the hypothalamic Mkrn3 mRNA expression pattern in mice correlated with a putative inhibitory input on puberty initiation. Indeed, the initiation of puberty depends on a decrease in factors that inhibit the release of GnRH combined with an increase in stimulatory factors. These recent human and animal findings suggest that MKRN3 plays an inhibitory role in the reproductive axis to represent a new pathway in pubertal regulation.
- Quality of life of patients with 46,XX and 46,XY disorders of sex development(2015) AMARAL, Rita Cassia; INACIO, Marlene; BRITO, Vinicius N.; BACHEGA, Tania A. S. S.; DOMENICE, Sorahia; ARNHOLD, Ivo J. P.; MADUREIRA, Guiomar; GOMES, Larissa; COSTA, Elaine M. F.; MENDONCA, Berenice B.Disorders of sex development (DSD) result from abnormalities in the complex process of sex determination and differentiation. An important consideration to guide the assignment of social sex in newborns with ambiguous genitalia is the quality of life (QoL) of these patients in adulthood. The rarity of most DSD conditions makes it difficult to conduct a long-term follow-up of affected patients through adulthood. This review of papers on the QoL of DSD patients evaluated in developing and developed countries by qualitative and quantitative instruments revealed a large spectrum of QoL, ranging from very poor to similar to, or even better than, the normal population. A more adequate QoL was found in patients from tertiary centres, indicating that the medical care of DSD patients should be multidisciplinary and carried out by specialized teams.
- Validation of an immunoassay for anti-Mullerian hormone measurements and reference intervals in healthy Brazilian subjects(2015) WOLOSZYNEK, Renata Reis; BRITO, Luciana Pinto; BATISTA, Marcelo Cidade; VALASSI, Helena Panteliou Lima; MENDONCA, Berenice Bilharinho; BRITO, Vinicius NahimeBackground Anti-Mullerian hormone is marker of ovarian and testicular reserve. The clinical use of this hormone requires proper standardization of reference intervals. The aims of this study were to validate the Anti-Mullerian hormone Gen II immunoassay, to establish Anti-Mullerian hormone reference intervals in healthy subjects, and to evaluate the influence of hormonal contraceptives, smoking, and body mass index on Anti-Mullerian hormone. Methods The validation of the Anti-Mullerian hormone Gen II assay (Beckman Coulter Company, TX, USA) was performed using a simplified protocol recommended by Clinical Laboratory Standard Institute. One-hundred and thirty-three healthy females and 120 males were prospectively selected for this study. Results The analytical and functional sensitivities of the Anti-Mullerian hormone Gen II immunoassay were 0.02 and 0.2ng/mL, respectively. Intra-assay coefficients ranged from 5.2 to 9.0%, whereas inter-assay precision ranged from 4.6 to 7.8% at different concentrations. In females, Anti-Mullerian hormone showed progressive decline with increasing age (r=-0.4, p<0.001), whereas in males, age showed no influence on Anti-Mullerian hormone concentrations. In females, Anti-Mullerian hormone concentrations did not differ between users and non-users of hormonal contraceptives, smokers, and non-smokers and obese and lean individuals. However, there was a negative and significant correlation between Anti-Mullerian hormone and body mass index in males (r=-0.3, p=0.008). Conclusions Anti-Mullerian hormone Gen II assay was reliable for determining serum Anti-Mullerian hormone concentrations. Anti-Mullerian hormone concentrations declined with aging and presented a wide inter-individual variability. The lack of influence of hormonal contraceptives, smoking, and obesity on Anti-Mullerian hormone in both sexes allowed us to refine the normative concentrations for the Brazilian population.