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1.
BMC Med Inform Decis Mak ; 20(1): 45, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32122371

RESUMO

BACKGROUND: Mammographic breast density is an important predictor of breast cancer, but its measurement has limitations related to subjectivity of visual evaluation or to difficult access for automatic volumetric measurement methods. Herein, we describe the design and clinical validation of Aguida, a software program for automated quantification of breast density from flat mammography images. MATERIALS AND METHODS: The software program was developed in MatLab. After image segmentation separating the background from the breast image, the operator positions a cursor defining a region of interest on the pectoralis major muscle from the mediolateral oblique view. Then, in the craniocaudal view, the threshold for separation of the dense tissue is based on the optical density of the pectoral muscle, and the proportion of dense tissue is calculated by the program. Mammograms obtained from 2 different occasions in 291 women were used for clinical evaluation. RESULTS: The intraclass correlation coefficient (ICC) between breast density measurements by the software and by a radiologist was 0.96, with a bias of only 0.67 percentage points and a 95% limit of agreement of 13.5 percentage points; the ICC was 0.94 in the interobserver reliability assessment by two radiologists with different experience; and the ICC was 0.98 in the intraobserver reliability assessment. The distribution among the density classes was close to the values obtained with the volumetric software. CONCLUSIONS: Measurement of breast density with the Aguida program from flat mammography images showed high agreement with the visual determination by radiologists, and high inter- and intra-observer reliability.


Assuntos
Densidade da Mama , Neoplasias da Mama/prevenção & controle , Mamografia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Validação de Programas de Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
2.
Clin Endocrinol (Oxf) ; 86(4): 480-487, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27978607

RESUMO

INTRODUCTION: The primary concern related to congenital adrenal hyperplasia (CAH) newborn screening (NBS) is the high rate of false-positive results (FPR) associated with prematurity; false-negative results (FNR) can also occur due to precocious sample collection. OBJECTIVE: To determine the neonatal 17-hydroxyprogesterone (N17OHP) normal range in newborns in Sao Paulo using different references according to age and birthweight (BW) and to establish the optimal NBS cut-off levels. METHODS: Neonatal 17-hydroxyprogesterone levels from 271 810 newborns (NBs) according to sample collection time (G1: 48-<72 h and G2: ≥72 h) and BW (≤1500 g, 1501-2000 g, 2001-2500 and >2500 g) were evaluated. N17OHP was measured by an fluoroimmunoassay, and serum 17OHP was measured by liquid chromatography-mass spectrometry. Affected and asymptomatic NBs with persistently increased 17OHP levels were submitted to CYP21A2-sequencing. RESULTS: Neonatal 17-hydroxyprogesterone levels in G1 were lower than G2 in all BW groups (P < 0·001). The FPR rate in G1/G2 was 0·2% using the 99·8th and 0·5% using the 99·5th percentile. The 99·8th percentile N17OHP value was the best cut-off for distinguishing between unaffected and affected NBs. Forty-four salt wasters, and five simple virilisers were diagnosed; N17OHP levels ranged from 93·3 to 2209·8 nmol/l, and no affected neonates with FNR were identified. The positive predictive value in G1 and G2 using the 99·8th percentile was 5·6% and 14·1%, respectively, and 2·3% and 7%, respectively, using the 99·5th percentile. Molecular tests identified two NBs with the nonclassical form among the 29 FPR. CONCLUSION: Neonatal 17-hydroxyprogesterone levels adjusted to sample collection age and birthweight reduced the FPR, and the use of N17OHP values based upon the 99·8th percentile improved the NBS efficacy.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Hiperplasia Suprarrenal Congênita/diagnóstico , Triagem Neonatal/métodos , 17-alfa-Hidroxiprogesterona/normas , Hiperplasia Suprarrenal Congênita/sangue , Fatores Etários , Peso ao Nascer , Coleta de Amostras Sanguíneas/métodos , Cromatografia Líquida , Reações Falso-Positivas , Fluorimunoensaio , Humanos , Recém-Nascido , Espectrometria de Massas , Valores de Referência
3.
Eur J Endocrinol ; 175(2): 107-16, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27185867

RESUMO

BACKGROUND: Most congenital adrenal hyperplasia (CAH) patients carry CYP21A2 mutations derived from conversion events involving the pseudogene, and the remaining carry new mutations. OBJECTIVE: To review causal mutations and genotype-phenotype correlation in 480 Brazilian patients. METHODS: DNA was extracted from 158 salt-wasters (SWs), 116 simple virilizing (SV), and 206 nonclassical (NC) patients. Fourteen point mutations were screened by allele-specific PCR, large rearrangements by Southern blotting/MLPA, and sequencing was performed in those with incomplete genotype. The gene founder effect was analyzed by microsatellite studies. Patients were divided into six genotypes (Null; A: <2%; B: 3-7%; C: >20% of residual enzymatic activity (EA); D: unknown EA; E: incomplete genotype). RESULTS: Targeted methodologies defined genotype in 87.6% of classical and in 80% of NC patients and the addition of sequencing in 100 and 83.5%, respectively. The most frequent mutations were p.V281L (26.6% of alleles), IVS2-13A/C>G (21.1%), and p.I172N (7.5%); seven rare mutations and one novel mutation (p.E351V) were identified. Gene founder effect was observed in all but one (p.W19X) mutation. Null, A, B, and C genotypes correlated with SW (88%), SW (70%), SV (98%), and NC forms (100%), respectively. In group D, the p.E351V mutation correlated with classical form and group E comprised exclusively NC-patients. ACTH-stimulated 17OHP level of 44.3ng/mL was the best cutoff to identify NC-patients carrying severe mutations. CONCLUSIONS: We identified a good genotype-phenotype correlation in CAH, providing useful data regarding prediction of disease's severity; moreover, we suggest that ACTH-stimulated 17OHP levels could predict carrier status for severe mutations. Sequencing is essential to optimize molecular diagnosis in Brazilian CAH patients.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Genótipo , Mutação Puntual , Esteroide 21-Hidroxilase/genética , Adolescente , Hiperplasia Suprarrenal Congênita/genética , Alelos , Brasil , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Humanos , Lactente , Recém-Nascido , Masculino , Técnicas de Diagnóstico Molecular , Fenótipo
4.
Arq Bras Endocrinol Metabol ; 51(6): 913-9, 2007 Aug.
Artigo em Português | MEDLINE | ID: mdl-17934657

RESUMO

Prader-Willi Syndrome (PWS) is a multisystemic genetic disease characterized by hypotonia, mental retardation, characteristic facial appearance, hyperphagia, and compulsive eating due to hypothalamic dysfunction. PWS is caused by loss of function of genes located in chromosome 15q11-q13, an area subject to genomic imprinting. Obesity is a major cause of increased morbidity and mortality among patients with PWS. The objective of this study was to analyze the therapeutic options available for the treatment of the obesity in PWS including pharmacological and surgical strategies.


Assuntos
Obesidade/terapia , Síndrome de Prader-Willi/complicações , Adolescente , Fármacos Antiobesidade/uso terapêutico , Cirurgia Bariátrica , Criança , Pré-Escolar , Feminino , Fluoxetina/uso terapêutico , Frutose/análogos & derivados , Frutose/uso terapêutico , Humanos , Lactente , Recém-Nascido , Masculino , Mazindol/uso terapêutico , Obesidade/etiologia , Obesidade/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Topiramato
5.
Arq. bras. endocrinol. metab ; 51(6): 913-919, ago. 2007. tab
Artigo em Português | LILACS | ID: lil-464282

RESUMO

A Síndrome de Prader-Willi (SPW) é uma doença complexa, multissistêmica, caracterizada por hipotonia, retardo mental, características dismórficas, hiperfagia e compulsão alimentar devido à disfunção hipotalâmica. SPW ocorre pela perda de função de genes localizados no cromossomo 15q11-13, região que sofre imprinting genômico. Obesidade é a principal causa de morbidade e mortalidade entre pacientes com SPW. O objetivo desta revisão é analisar as opções terapêuticas disponíveis para o tratamento da obesidade na SPW, incluindo a terapia farmacológica e o tratamento cirúrgico.


Prader-Willi Syndrome (PWS) is a multisystemic genetic disease characterized by hypotonia, mental retardation, characteristic facial appearance, hyperphagia, and compulsive eating due to hypothalamic dysfunction. PWS is caused by loss of function of genes located in chromosome 15q11-q13, an area subject to genomic imprinting. Obesity is a major cause of increased morbidity and mortality among patients with PWS. The objective of this study was to analyze the therapeutic options available for the treatment of the obesity in PWS including pharmacological and surgical strategies.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Obesidade/terapia , Síndrome de Prader-Willi/complicações , Fármacos Antiobesidade/uso terapêutico , Cirurgia Bariátrica , Fluoxetina/uso terapêutico , Frutose/análogos & derivados , Frutose/uso terapêutico , Mazindol/uso terapêutico , Obesidade/etiologia , Obesidade/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
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