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1.
Genet Mol Biol ; 39(2): 199-202, 2016 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-27223487

RESUMEN

Germline TP53 mutations are associated with Li-Fraumeni syndrome (LFS), a disease that predisposes carriers to a wide variety of early onset tumors. In southern and southeastern Brazil, a high frequency of a germline TP53 mutation, p.R337H, was diagnosed in 0,3% of the population due to a founder effect. Carriers are at risk for developing cancer but the penetrance is lower than in typical DNA binding domain mutations. To date, only a few families were detected and diagnosis of carriers remains a challenge. Therefore, the inclusion of additional criteria to detect p.R337H carriers is necessary for the Brazilian population. We assessed the A.C. Camargo Cancer Center Oncogenetics Department database in search of common characteristics associated with p.R337H families that did not fulfill LFS/LFL clinical criteria. Among 42 p.R337H families, three did not meet any LFS/LFL criteria. All cases were young female patients with breast cancer diagnosed before age 45 and with no family history of LFS linked-cancers. Our results suggest that screening for the germline TP53 p.R337H mutation should be indicated, along with BRCA1 and BRCA2 genetic testing, for this group of patients, especially in the South and Southeast of Brazil.

2.
Int J Mol Sci ; 16(4): 8988-96, 2015 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-25913378

RESUMEN

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by DNA repair defects that cause photophobia, sunlight-induced cancers, and neurodegeneration. Prevalence of germline mutations in the nucleotide excision repair gene XPA vary significantly in different populations. No Brazilian patients have been reported to carry a germline mutation in this gene. In this study, the germline mutational status of XPA was determined in Brazilian patients exhibiting major clinical features of XP syndrome. The study was conducted on 27 unrelated patients from select Brazilian families. A biallelic inactivating transition mutation c.619C>T (p.Arg207Ter) was identified in only one patient with a history of neurological impairment and mild skin abnormalities. These findings suggest that XP syndrome is rarely associated with inherited disease-causing XPA mutations in the Brazilian population. Additionally, this report demonstrates the effectiveness of genotype-phenotype correlation as a valuable tool to guide direct genetic screening.


Asunto(s)
Proteína de la Xerodermia Pigmentosa del Grupo A/genética , Xerodermia Pigmentosa/genética , Adolescente , Brasil , Análisis Mutacional de ADN , Femenino , Mutación de Línea Germinal , Humanos , Masculino , Prevalencia , Xerodermia Pigmentosa/epidemiología
3.
Carcinogenesis ; 35(4): 807-15, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24336192

RESUMEN

Germline TP53 mutations predispose to multiple cancers defining Li-Fraumeni/Li-Fraumeni-like syndrome (LFS/LFL), a disease with large individual disparities in cancer profiles and age of onset. G-quadruplexes (G4s) are secondary structural motifs occurring in guanine tracks, with regulatory effects on DNA and RNA. We analyzed 85 polymorphisms within or near five predicted G4s in TP53 in search of modifiers of penetrance of LFS/LFL in Brazilian cancer families with (n = 35) or without (n = 110) TP53 mutations. Statistical analyses stratified on family structure showed that cancer tended to occur ~15 years later in mutation carriers who also carried the variant alleles of two polymorphisms within predicted G4-forming regions, rs17878362 (TP53 PIN3, 16 bp duplication in intron 3; P = 0.082) and rs17880560 (6 bp duplication in 3' flanking region; P = 0.067). Haplotype analysis showed that this inverse association was driven by the polymorphic status of the remaining wild-type (WT) haplotype in mutation carriers: in carriers with a WT haplotype containing at least one variant allele of rs17878362 or rs17880560, cancer occurred ~15 years later than in carriers with other WT haplotypes (P = 0.019). No effect on age of cancer onset was observed in subjects without a TP53 mutation. The G4 in intron 3 has been shown to regulate alternative p53 messenger RNA splicing, whereas the biological roles of predicted G4s in the 3' flanking region remain to be elucidated. In conclusion, this study demonstrates that G4 polymorphisms in haplotypes of the WT TP53 allele have an impact on LFS/LFL penetrance in germline TP53 mutation carriers.


Asunto(s)
Edad de Inicio , G-Cuádruplex , Genes p53 , Tamización de Portadores Genéticos , Neoplasias/genética , Polimorfismo Genético , Secuencia de Bases , ADN , Humanos , Datos de Secuencia Molecular
4.
Breast Cancer Res ; 14(1): R24, 2012 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-22314128

RESUMEN

INTRODUCTION: Genetic factors predisposing individuals to cancer remain elusive in the majority of patients with a familial or clinical history suggestive of hereditary breast cancer. Germline DNA copy number variation (CNV) has recently been implicated in predisposition to cancers such as neuroblastomas as well as prostate and colorectal cancer. We evaluated the role of germline CNVs in breast cancer susceptibility, in particular those with low population frequencies (rare CNVs), which are more likely to cause disease." METHODS: Using whole-genome comparative genomic hybridization on microarrays, we screened a cohort of women fulfilling criteria for hereditary breast cancer who did not carry BRCA1/BRCA2 mutations. RESULTS: The median numbers of total and rare CNVs per genome were not different between controls and patients. A total of 26 rare germline CNVs were identified in 68 cancer patients, however, a proportion that was significantly different (P = 0.0311) from the control group (23 rare CNVs in 100 individuals). Several of the genes affected by CNV in patients and controls had already been implicated in cancer. CONCLUSIONS: This study is the first to explore the contribution of germline CNVs to BRCA1/2-negative familial and early-onset breast cancer. The data suggest that rare CNVs may contribute to cancer predisposition in this small cohort of patients, and this trend needs to be confirmed in larger population samples.


Asunto(s)
Carcinoma Ductal de Mama/genética , Variaciones en el Número de Copia de ADN , Mutación de Línea Germinal , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios de Cohortes , Hibridación Genómica Comparativa , Femenino , Dosificación de Gen , Humanos , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Estadísticas no Paramétricas , Adulto Joven
5.
BMC Cancer ; 12: 237, 2012 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-22691290

RESUMEN

BACKGROUND: Li-Fraumeni (LFS) and Li-Fraumeni-like (LFL) syndromes are associated to germline TP53 mutations, and are characterized by the development of central nervous system tumors, sarcomas, adrenocortical carcinomas, and other early-onset tumors. Due to the high frequency of breast cancer in LFS/LFL families, these syndromes clinically overlap with hereditary breast cancer (HBC). Germline point mutations in BRCA1, BRCA2, and TP53 genes are associated with high risk of breast cancer. Large rearrangements involving these genes are also implicated in the HBC phenotype. METHODS: We have screened DNA copy number changes by MLPA on BRCA1, BRCA2, and TP53 genes in 23 breast cancer patients with a clinical diagnosis consistent with LFS/LFL; most of these families also met the clinical criteria for other HBC syndromes. RESULTS: We found no DNA copy number alterations in the BRCA2 and TP53 genes, but we detected in one patient a 36.4 Kb BRCA1 microdeletion, confirmed and further mapped by array-CGH, encompassing exons 9-19. Breakpoints sequencing analysis suggests that this rearrangement was mediated by flanking Alu sequences. CONCLUSION: This is the first description of a germline intragenic BRCA1 deletion in a breast cancer patient with a family history consistent with both LFL and HBC syndromes. Our results show that large rearrangements in these known cancer predisposition genes occur, but are not a frequent cause of cancer susceptibility.


Asunto(s)
Proteína BRCA1/genética , Eliminación de Gen , Genes BRCA1 , Síndrome de Li-Fraumeni/genética , Adulto , Neoplasias de la Mama/genética , Aberraciones Cromosómicas , Mapeo Cromosómico , Variaciones en el Número de Copia de ADN , Femenino , Humanos , Persona de Mediana Edad , Linaje
6.
Cancer Imaging ; 18(1): 27, 2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-30107858

RESUMEN

BACKGROUND: Li-Fraumeni syndrome (LFS) is an autosomal dominant disease that is associated with germline TP53 mutations and it predisposes affected individuals to a high risk of developing multiple tumors. In Brazil, LFS is characterized by a different pattern of TP53 variants, with the founder TP53 p.R337H mutation being predominant. The adoption of screening strategies to diagnose LFS in its early stages is a major challenge due to the diverse spectrum of tumors that LFS patients can develop. The purpose of this study was to evaluate two rounds of whole-body magnetic resonance imaging (WB-MRI) which were conducted as a screening strategy for LFS patients. METHODS: Over a 4-year period, 59 LFS patients underwent two rounds of WB-MRI. Each MRI was characterized as positive or negative, and positive cases were further investigated to establish a diagnosis. The parameters used to evaluate the WB-MRI results included: positive rate, number of invasive investigations of positive results, and cancer detection rate. RESULTS: A total of 118 WB-MRI scans were performed. Positive results were associated with 11 patients (9.3%). Seven of these patients (11.8%) were identified in the first round of screening and 4 patients (6.7%) were identified in the second round of screening. Biopsies were performed in three cases (2.5%), two (3.4%) after the first round of screening and one (1.7%) after the second round of screening. The histopathological results confirmed a diagnosis of cancer for all three cases. There was no indication of unnecessary invasive procedures. CONCLUSIONS: WB-MRI screening of LFS carriers diagnosed cancers in their early stages. When needed, positive results were further examined with non-invasive imaging techniques. False positive results were less frequent after the first round of WB-MRI screening.


Asunto(s)
Síndrome de Li-Fraumeni/diagnóstico por imagen , Imagen por Resonancia Magnética , Imagen de Cuerpo Entero , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Front Genet ; 9: 161, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29868112

RESUMEN

Pathogenic variants in known breast cancer (BC) predisposing genes explain only about 30% of Hereditary Breast Cancer (HBC) cases, whereas the underlying genetic factors for most families remain unknown. Here, we used whole-exome sequencing (WES) to identify genetic variants associated to HBC in 17 patients of Brazil with familial BC and negative for causal variants in major BC risk genes (BRCA1/2, TP53, and CHEK2 c.1100delC). First, we searched for rare variants in 27 known HBC genes and identified two patients harboring truncating pathogenic variants in ATM and BARD1. For the remaining 15 negative patients, we found a substantial vast number of rare genetic variants. Thus, for selecting the most promising variants we used functional-based variant prioritization, followed by NGS validation, analysis in a control group, cosegregation analysis in one family and comparison with previous WES studies, shrinking our list to 23 novel BC candidate genes, which were evaluated in an independent cohort of 42 high-risk BC patients. Rare and possibly damaging variants were identified in 12 candidate genes in this cohort, including variants in DNA repair genes (ERCC1 and SXL4) and other cancer-related genes (NOTCH2, ERBB2, MST1R, and RAF1). Overall, this is the first WES study applied for identifying novel genes associated to HBC in Brazilian patients, in which we provide a set of putative BC predisposing genes. We also underpin the value of using WES for assessing the complex landscape of HBC susceptibility, especially in less characterized populations.

8.
Stud Health Technol Inform ; 217: 106-10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26294460

RESUMEN

Researchers working in fields intending to generate beneficial socio-economic impacts are increasingly challenged to demonstrate evidence that the findings from their studies have value to audiences beyond the peer academic community. These diverse and diffuse target audiences may include clinicians, consumers, manufacturers and information brokers. This paper summarizes a project that designed, constructed and validated a web-based instrument for collecting and analyzing self-reported data on knowledge use. The Level Of Knowledge Use Survey instrument is valid and reliable for measuring uptake of new knowledge and for tracking changes in level of knowledge use over time.


Asunto(s)
Encuestas y Cuestionarios , Investigación Biomédica Traslacional/métodos , Humanos , Internet , Reproducibilidad de los Resultados , Proyectos de Investigación
9.
Front Oncol ; 5: 38, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25745605

RESUMEN

PURPOSE: To evaluate the effectiveness of (18)F-Fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) for detecting early cancer in carriers of germline TP53 mutation, the genetic defect underlying Li-Fraumeni and related syndromes, which predisposes to many forms of cancer throughout life. PATIENTS AND METHODS: A total of 30 adult patients from six families with germline TP53 mutations were recruited. These patients did not have a diagnosis of cancer in the 24 months preceding the study. Anomalous concentrations from whole-body (18)F-FDG-PET/CT were assessed by two independent experts. Suspicious lesions were excised and subjected to pathological examination. RESULTS: A total of 6/30 patients showed abnormal (18)F-FDG-concentration. Confirmation studies revealed three cases of cancer, including one lung cancer, one ovarian cancer, and one disseminated breast cancer. Three patients had non-malignant lesions (one Bartholin's cyst and two cases of reactive lymph nodes). CONCLUSION: (18)F-FDG-PET/CT is effective in detecting cancer in subjects who are asymptomatic according to current screening guidelines. These results further suggest that (18)F-FDG-PET/CT is an appropriate method for surveillance of cancer risk in TP53 mutation carriers.

10.
Cancer Genet ; 208(6): 341-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25935441

RESUMEN

Li-Fraumeni syndrome (LFS) is a hereditary disorder that predisposes patients to several types of cancer and is associated with TP53 germline mutations. Turner syndrome (TS) is one of the most common aneuploidies in women. Patients with TS have a higher risk of developing cancer, although multiple malignant tumors are extremely rare. Herein, we describe a patient with a 45,X/46,XX karyotype with no classic phenotype of TS. She presented with a clinical diagnosis of Li-Fraumeni-like syndrome (LFL), showing papillary thyroid carcinoma and fibrosarcoma of the left flank, and had no TP53 germline mutations. Genome-wide analysis of copy number variations (CNVs) was assessed in DNA from peripheral blood cells and saliva. A total of 109 rare CNVs in the blood cells, including mosaic loss of the X chromosome (76% of cells), were identified. In saliva, three rare CNVs were detected, all of them were also detected in the blood cells: loss of 8q24.11 (EXT1), gain of 16q24.3 (PRDM7 and GAS8), and the mosaic loss of the X chromosome (50% of cells). Results of conventional G-banding confirmed the 45,X/46,XX karyotype. Surprisingly, the patient presented with an apparently normal phenotype. The PRDM and GAS8 genes are potential candidates to be associated with the risk of developing cancer in this LFL/TS patient.


Asunto(s)
Carcinoma/genética , Proteínas del Citoesqueleto/genética , Fibrosarcoma/genética , Síndrome de Li-Fraumeni/genética , Proteínas de Neoplasias/genética , Neoplasias de la Tiroides/genética , Carcinoma Papilar , Cromosomas Humanos X/genética , Variaciones en el Número de Copia de ADN/genética , Femenino , Predisposición Genética a la Enfermedad , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Cariotipo , Persona de Mediana Edad , Cáncer Papilar Tiroideo , Proteína p53 Supresora de Tumor/genética , Síndrome de Turner/genética
11.
SAGE Open Med ; 2: 2050312114554331, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26770743

RESUMEN

OBJECTIVES: Uptake of new knowledge by diverse and diffuse stakeholders of health-care technology innovations has been a persistent challenge, as has been measurement of this uptake. This article describes the development of the Level of Knowledge Use Survey instrument, a web-based measure of self-reported knowledge use. METHODS: The Level of Knowledge Use Survey instrument was developed in the context of assessing effectiveness of knowledge communication strategies in rehabilitation technology. It was validated on samples representing five stakeholder types: researchers, manufacturers, clinician-practitioners, knowledge brokers, and consumers. Its structure is broadly based on Rogers' stages of innovation adoption. Its item generation was initially guided by Hall et al's Levels of Use framework. Item selection was based on content validity indices computed from expert ratings (n 1 = 4; n 2 = 3). Five representative stakeholders established usability of the web version. The version included 47 items (content validity index for individual items >0.78; content validity index for a scale or set of items >0.90) in self-reporting format. Psychometrics were then established for the version. RESULTS: Analyses of data from small (n = 69) and large (n = 215) samples using the Level of Knowledge Use Survey instrument suggested a conceptual model of four levels of knowledge use-Non-awareness, Awareness, Interest, and Use. The levels covered eight dimensions and six user action categories. The sequential nature of levels was inconclusive due to low cell frequencies. The Level of Knowledge Use Survey instrument showed adequate content validity (≈ 0.88; n = 3) and excellent test-retest reliability (1.0; n = 69). It also demonstrated good construct validity (n = 215) for differentiating among new knowledge outputs (p < 0.001) and among stakeholder types (0.001 < p ≤ 0.013). It showed strong responsiveness to change between baseline and follow-up testing (0.001 < p ≤ 0.002; n = 215). CONCLUSION: The Level of Knowledge Use Survey instrument is valid and reliable for measuring uptake of innovations across diffuse stakeholders of rehabilitation technologies and therefore also for tracking changes in knowledge use.

12.
Fam Cancer ; 13(4): 645-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25023876

RESUMEN

Approximately 10 % of all cutaneous melanoma cases occur in a familial context. The major susceptibility gene for familial melanoma is CDKN2A. In Latin America, genetic studies investigating melanoma predisposition are scarce. The aim of this work was to investigate germline CDKN2A point mutations and genomic rearrangements in a cohort of 59 Brazilian melanoma-prone patients. Screening of CDKN2A alterations was performed by sequencing and multiplex ligation probe amplification. Germline CDKN2A mutations affecting p16(INK4a) were detected in 8 unrelated probands (13.6 %), including 7 familial cases and one patient with multiple melanomas; 4 out of 8 mutation carriers met the criteria for familial melanoma and had multiple primary lesions. Although this study adds to the literature on melanoma susceptibility in Latin America, it is limited by the small size of the cohort. Our findings suggest that stringent inclusion criteria led to a substantially increased rate of CDKN2A mutation detection. This consideration should be taken into account when referring patients for genetic screening in a setting of limited budget, such as in developing countries.


Asunto(s)
Genes p16 , Predisposición Genética a la Enfermedad/genética , Melanoma/genética , Adulto , Brasil , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Femenino , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex , Neoplasias Cutáneas , Adulto Joven , Melanoma Cutáneo Maligno
13.
Enferm. foco (Brasília) ; 9(2): 66-72, mai. 2018. tab
Artículo en Portugués | LILACS, BDENF - enfermagem (Brasil) | ID: biblio-1028359

RESUMEN

Objetivo: verificar tecnologias de enfermagem utilizadas no manejo da dor em recém-nascidos de uma Unidade de Terapia Intensiva Neonatal. Metodologia: pesquisa quantitativa, descritiva, exploratória, realizada em uma Maternidade Pública Estadual no interior da Paraíba, com 12 técnicos de enfermagem e 5 enfermeiros. Utilizado um questionário estruturado para coleta de dados e a análise feita por meio do Microsoft Excel. Resultados: foi observado que a utilização de escalas de dor não faz parte da rotina e o choro foi o parâmetro mais utilizado para reconhecer a dor no neonato. Conclusão: é necessário ampliar as discussões sobre essa temática a partir da sistematização e educação permanente nos serviços de cuidados intensivos ao neonato.


Objective: verifying the nursing technologies used in the management of pain in newborns in a Neonatal Intensive Care Unit. Methodology: this is a descriptive exploratory quantitative research, performed in a Public Maternity placed in interior of Paraiba’s State, with 12 nursing technicians and 5 nurses, a structured questionnaire was used for the collection of data the analysis made through the Microsoft Excel. Results: it was noticed that the use of pain scales is not part of the routine and the crying was the most used parameter by the nursing team to recognize pain in the neonate. Conclusion: it is necessary to broaden the discussions on this subject from the systematization and continuous education in the neonatal intensive care services.


Objetivo: verificar tecnologías de enfermería utilizadas en el control del dolor en recién nacidos de una unidad de cuidados intensivos neonatales. Metodología: pesquisa cuantitativa, descriptiva y exploratória, realizada en una Maternidad Pública Estatal en el interior de la Paraiba, con 12 tecnicos de enfermería y 5 enfermeros. Fue utilizado un cuestionario estructurado para la recogida de datos y la análisis hecha por medio del Microsoft Excel. Resultados: se observó que el uso de escalas de dolor no era la rutina y el llanto fue el parámetro mas usado para reconocer el dolor de neonato. Conclusión: es necesario aumentar las discusiones sobre ese tema a partir de la sistematización y educación permamente en los servicios de cuidados intensivos al neonato.


Asunto(s)
Masculino , Femenino , Humanos , Recién Nacido , Enfermería Neonatal , Manejo del Dolor , Tecnología Biomédica , Unidades de Cuidado Intensivo Neonatal
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